GCSE/IGCSE Chemistry Question Bank with Answers

GCSE CHEMISTRY

ACIDS, BASES & SALTS

High Demand Questions

QUESTIONSHEET 1

A food scientist checked the quality of a bottle of vinegar. He took 50 cm3 of the vinegar and found out how much sodium hydroxide was needed to neutralise it. (a) (i)

Explain what is meant by ‘neutralise’.

......................................................................................................................................................................... [1] (ii) What apparatus could the scientist have used to measure the amount of sodium hydroxide needed?

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......................................................................................................................................................................... [1] He also tested some ethanoic acid solution. Ethanoic acid is the acid which is found in vinegar. His results are shown below.

30

ethanoic acid 10

e.c

vinegar 50

10

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volume used/cm3 volume of NaOH needed to neutralise/cm3

The ethanoic acid solution contained 10 g of acid in every 100 cm3 of solution. (b) (i)

How many grams of ethanoic acid are there in 10 cm3 of solution?

ma

......................................................................................................................................................................... [1] (ii) Work out how many grams of ethanoic acid are in 50 cm3 of the vinegar.

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.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

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(iii) What must you assume is kept constant to allow you to work out the answer to (ii) ? ......................................................................................................................................................................... [1] A label on the bottle of vinegar states that it contains 8 g of ethanoic acid in 100 cm3 of vinegar. (c)

Using your answer to (b)(ii) work out whether the answer on the bottle is correct. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 2

copper

nickel

zinc

Use the observations from above to complete the following reactivity series.

e.c

(a)

magnesium

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Small pieces of the metals copper, magnesium, nickel and zinc were placed in test tubes containing small quantities of hydrochloric acid. The following results were observed.

1. ........................................................................................................................................................ most reactive

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2. .............................................................................................................................................................................. 3. ..............................................................................................................................................................................

(b) (i)

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4. .........................................................................................................................................................least reactive [2] What is the name of the gas produced in the above reactions?

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......................................................................................................................................................................... [1] (ii) Describe the test and result you would use to identify this gas.

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.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

The reaction between the metals and the hydrochloric acid also produces a chemical compound known as a salt. (i)

What is the name of the salt formed in the reaction between magnesium and hydrochloric acid?

......................................................................................................................................................................... [1] (ii) What type of bonding is present in this salt? ......................................................................................................................................................................... [1] (iii) This salt is a solid at room temperature. Explain why a salt has a high melting and boiling point. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 3

(a)

The metal sodium burns in limited oxygen with a bright yellow flame to form sodium oxide. (i)

Write a word equation for the reaction between sodium and oxygen.

......................................................................................................................................................................... [1] (ii) What is the formula of sodium oxide? 2(A sodium ion is Na+ and an oxide ion is O )

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......................................................................................................................................................................... [1] (iii) Predict whether sodium oxide is a solid, liquid or gas at room temperature.

e.c

......................................................................................................................................................................... [1] (iv) Sodium oxide dissolves readily in water. What colour would the resulting solution turn pH paper?

(b)

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......................................................................................................................................................................... [1] Sulphur dioxide is produced when coal is burnt and is responsible for the formation of acid rain. (i)

Complete the following equation and put in the missing state symbol.

ma

S (s) + ____ (g) → SO2 ____

[2]

(ii) Acid rain is a weak acid. Predict what pH it would have if it was tested with pH paper.

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......................................................................................................................................................................... [1] (iii) Write down two problems which acid rain can cause.

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1. .......................................................................................................................................................................... 2............................................................................................................................................................................ [2]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 4

The following experiment was carried out using concentrated ammonia solution and concentrated hydrochloric acid. white smoke forms here

Ammonia contains the elements hydrogen and nitrogen and has the chemical formula NH3. (i)

Name the type of bonding that exists in ammonia

e.c

(a)

cotton wool soaked in concentrated hydrochloric acid

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cotton wool soaked in concentrated ammonia solution

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......................................................................................................................................................................... [1]

he

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(ii) Use the Periodic Table to draw a 'dot and cross' diagram to show the bonding in a molecule of ammonia. You need only show the electrons in the outer energy level.

[2]

(iii) Explain why ammonia has a low boiling point.

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.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (b)

The ammonia and hydrogen chloride gases meet and react to form the ring of white smoke which is shown in the diagram. (i)

Explain, in terms of the particles of the gases, why the gases meet.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Explain why the ring of white smoke forms nearer to the concentrated hydrochloric acid. ......................................................................................................................................................................... [1] (iii) What is the name of the chemical formed when ammonia and hydrogen chloride react? ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 5

The diagram below shows an experiment to measure the rate of reaction between calcium carbonate and sulphuric acid.

gas syringe

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Calcium calcium carbonate carbonate sulphuric acid

The reaction between calcium carbonate and sulphuric acid produces a chemical compound called a salt, a gas and water. (i)

e.c

(a)

The gas produced can be identified using limewater. Name the gas and the result of this test.

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Name of gas ............................................................................................................................................... Result of test ......................................................................................................................................... [2] (ii) What is the name of the salt produced?

(b)

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......................................................................................................................................................................... [1] The experiment was repeated with exactly the same volume of sulphuric acid and the same mass of calcium carbonate. This time the calcium carbonate used was a powder. What happens to the rate of the reaction?

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(i)

......................................................................................................................................................................... [1] (ii) Use the idea of particles to explain your answer to (b) (i).

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.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

The experiment was repeated but with magnesium metal instead of calcium carbonate and a different salt and a different gas were produced.

(i)

What gas is produced in the reaction between magnesium and sulphuric acid?

......................................................................................................................................................................... [1] (ii) Describe the test you would use to identify this gas and the result that you would obtain. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) Write down one use in industry of this gas. ......................................................................................................................................................................... [1] TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 6

The table below shows the colours of various indicators at different pH values. indicator bromophenol blue phenolphthalein methyl orange thymol blue

colour 1 yellow colourless red yellow

pH 3 8 3 6

colour 2 blue pink yellow blue

pH 4.5 10 4.5 7.5

Complete the table below to show colours of the indicators in the solutions. colour

[4]

Name one indicator which turns the same colour in both ethanoic acid and sodium hydroxide

ma

(b) (i)

solution hydrochloric acid ethanoic acid ammonia solution sodium hydroxide

e.c

indicator bromophenol blue phenolphthalein methyl orange thymol blue

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(a)

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Hydrochloric acid has a pH of 1.0 and ethanoic acid has a pH of 5.0 Ammonia solution has a pH of 10.0 and sodium hydroxide has a pH of 12.5

......................................................................................................................................................................... [1] (ii) Which two indicators turn the same colour in hydrochloric acid?

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..............................................................................................................................................................................

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......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY



QUESTIONSHEET 7

Slaked lime is used raise the pH of soil. (a)

What is the chemical name for slaked lime? ......................................................................................................................................................................... [1] The recommended amount to use is 125 g per square metre of soil. How much slaked lime would you need to apply to a rectangular garden which measured 10 metres by 8 metres?

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(b)

.............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

......................................................................................................................................................................... [2] Less calcium oxide than slaked lime is needed to treat the same garden. Why would the gardener prefer to use slaked lime?

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(c)

......................................................................................................................................................................... [1] (d) (i)

Write an equation for the reaction of slaked lime with nitric acid.

ma

......................................................................................................................................................................... [2] (ii) How much slaked lime is needed to neutralise 63 g of nitric acid? (Ar: H=1; N=14; O=16 Ca=40)

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.............................................................................................................................................................................. ..............................................................................................................................................................................

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......................................................................................................................................................................... [3]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 8

Sulphur dioxide reacts with chlorine, in the presence of water, to produce a mixture of hydrochloric and sulphuric acids. (a)

Complete the equation for the reaction. SO2 + Cl2 + __H2O Æ ______ + _______

This reaction can be used to reduce the amount of chlorine in water. If a bottle of tap water contained 2 mg of chlorine, how much sulphur dioxide must be added to reduce this to 1 mg? (Ar: O=16; S=32; Cl=35.5)

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(b)

[2]

..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

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......................................................................................................................................................................... [3] The concentration of a solution can be expressed in grams per cubic decimetre (g/dm3). To calculate this you must divide the amount of substance dissolved (g) by the volume of the solution (dm3).

A B

ma

Which of the following has the greater concentration? Show your working. 10 g of potassium hydroxide in 2 dm3 of solution. 50 g of potassium hydroxide in 5 dm3 of solution

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.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

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(c)

......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY


QUESTIONSHEET 9

Medium Demand Questions

The pH of chemicals found around the home may be tested using pH paper. Some typical results are shown below.

pH

1

2 ↓

lemon juice

4 ↓

5

6 È

7

8

9

10

orange juice washing-up liquid

11

12 ↓

13

14

oven cleaner

Answer the following questions using the above information. (i)

What is the pH of oven cleaner?

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(a)

3

(ii) Which is the most acidic solution?

e.c

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1]

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(iii) What would be the pH of a neutral solution?

......................................................................................................................................................................... [1] Vinegar was also tested using pH paper and found to have a pH of 4.1. What colour did the pH paper become?

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(b)

......................................................................................................................................................................... [1]

(i)

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When a wasp stings someone its injects a liquid in the person's skin. An old fashioned remedy for wasp stings is to rub vinegar on them. Suggest the pH of the liquid which wasps inject into the skin.

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(c)

......................................................................................................................................................................... [1] (ii) What name is given to the reaction which happens between this liquid and the vinegar? ......................................................................................................................................................................... [1] (iii) Name the colourless, tasteless liquid that is produced in this reaction. ......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY



QUESTIONSHEET 10

Some people suffer from acid indigestion when their stomach produces excess stomach acid. The label on a household brand of indigestion tablets says that it contains magnesium carbonate. (a)

Magnesium carbonate is insoluble in water. When mixed with water, what colour would it turn pH paper? ......................................................................................................................................................................... [1] The instructions on the packet suggest that 1 or 2 tablets are chewed as required. (i)

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(b)

What name is given to the reaction which happens between the excess acid and the indigestion tablet?

......................................................................................................................................................................... [1] Explain why the instructions suggest that the tablets are chewed when taken.

e.c

(ii)

..............................................................................................................................................................................

The acid present in the stomach is called hydrochloric acid. Hydrochloric acid, HCl, reacts with magnesium carbonate, MgCO3, to produce magnesium chloride, carbon dioxide and water.

(i)

Complete and balance the equation for this reaction.

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(c)

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......................................................................................................................................................................... [2]

___HCl (aq) + MgCO3(s) → MgCl2 (aq) + ___ (g) + H2O (l) Limewater can be used to test for carbon dioxide. What is the result of this test?

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(ii)

[2]

(iii)

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......................................................................................................................................................................... [1] Use these relative atomic masses: C = 12; O = 16; Mg = 24 to calculate the relative formula mass of magnesium carbonate.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY


QUESTIONSHEET 11

Medium Demand Questions (a)

In an experiment ammonia solution, an alkali, was added to nitric acid. apparatus A

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ammonia solution ammonium hydroxide

nitric acid

What is the name of apparatus A?

e.c

(i)

......................................................................................................................................................................... [1]

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(ii) What is the name of the reaction when the acid reacts with the alkali? ......................................................................................................................................................................... [1] (iii) What is the pH when just enough ammonia solution is added to react with all the nitric acid?

(b) (i)

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......................................................................................................................................................................... [1] What is the ion which is present in any solution of acid?

......................................................................................................................................................................... [1]

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(ii) What is the ion which is present in any solution of alkali? ......................................................................................................................................................................... [1]

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(iii) Write the simplest ionic equation which represents the above reaction. ......................................................................................................................................................................... [1] (c)

The following label is found on the bottle containing the nitric acid.

(i)

What does the label tell you about the nitric acid?

......................................................................................................................................................................... [1] (ii) Suggest two precautions which should be taken when using the nitric acid in the experiment. 1. ..................................................................................................................................................................... [1] 2. ..................................................................................................................................................................... [1] TOTAL / 9

GCSE CHEMISTRY


QUESTIONSHEET 12


Below are the chemical formulae of four acids. HCl (i)

H2SO4

HNO3

CH3COOH

What colour would they all turn a solution of litmus?

......................................................................................................................................................................... [1]

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(ii) Write down the name of the ion present in solutions of all the acids. ......................................................................................................................................................................... [1] Below are the chemical formulae of four alkalis. NaOH (i)

KOH

Mg(OH)2

NH4OH

e.c

(b)

What colour would they all turn a solution of litmus?

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......................................................................................................................................................................... [1] (ii) Write down the name of the ion present in solutions of all the alkalis.

(c)

ma

......................................................................................................................................................................... [1] A solution of sulphuric acid can be used to neutralise a solution of sodium hydroxide. What is the pH of the solution when it is exactly neutral?

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(i)

......................................................................................................................................................................... [1]

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(ii) What is the name of the salt formed in the neutralisation reaction? ......................................................................................................................................................................... [1] (iii) Balance the following symbol equation for the reaction. H2SO4 (aq) + ____ NaOH (aq) → Na2SO4 (aq) + ____ H2O (l) (d)

[2]

When nitric acid neutralises ammonium hydroxide the salt formed is called ammonium nitrate. Give one important use of ammonium nitrate. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 13

Many power stations in the UK burn coal to produce electricity. Coal is a fossil fuel. Describe how the coal is formed. .............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

(b)

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......................................................................................................................................................................... [3] Fossil fuels, such as coal, contain sulphur as an impurity. When the coal is burnt the sulphur is oxidised. Explain what is meant by the term 'oxidised'.

e.c

(i)

..............................................................................................................................................................................

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......................................................................................................................................................................... [1] (ii) What is the name of the gas formed when the sulphur is oxidised? ......................................................................................................................................................................... [1] Write a symbol equation for what happens when this gas reacts with rain water.

ma

(c)

......................................................................................................................................................................... [2]

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Explain why acid rain can erode limestone.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

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(d)

TOTAL / 9

GCSE CHEMISTRY


QUESTIONSHEET 14


Below is information about six chemicals. state at 20 °C gas liquid solid solid solid solid

pH in water 1 7 4 8 14 no reaction

(a)

e.c

Use the table to write the letter of the chemical substance which:

reaction with acid none none none forms a salt, carbon dioxide and water forms a salt and water fizzes

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chemical A B C D E F

forms the most strongly acidic solution.

(b)

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......................................................................................................................................................................... [1] forms a neutral solution.

......................................................................................................................................................................... [1] forms a solution which turns pH paper orange.

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(c)

......................................................................................................................................................................... [1] is a metal .

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(d)

......................................................................................................................................................................... [1] is a carbonate.

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(e)

......................................................................................................................................................................... [1] (f)

is water.

......................................................................................................................................................................... [1] (g)

is sulphur dioxide.

......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY


QUESTIONSHEET 15


Antacid tablets are used to treat indigestion, which is caused by excess acid in the stomach. Details of four solids, which are used to neutralise stomach acid, are shown in the table below. Name of solid magnesium carbonate

Formula CaCO3 Mg(OH) 2 Al(OH) 3

magnesium hydroxide aluminium hydroxide

Reaction with acid fizzes does not fizz does not fizz

Cost per gram 16.0 p 11.0 p 7.5 p 22.0 p

Complete the table.

(b)

Complete the equation for the reaction of magnesium hydroxide with hydrochloric acid. Mg(OH) 2 + 2HCl

Æ

+ H2O

[1]

An experiment was carried out to find out how much acid was needed to neutralise one gram of each of the solids. The solid was put into a flask with water and an indicator, then acid was added. Describe how you would find out the exact amount of acid needed.

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(i)

e.c

(c)

[3]

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(a)

.............................................................................................................................................................................. ..............................................................................................................................................................................

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......................................................................................................................................................................... [2] (ii) Why is it important to use the same concentration of acid each time?

Another way to compare the solids is to find out how much solid is needed to neutralise 20 cm3 of acid. The results are shown below.

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(d)

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......................................................................................................................................................................... [1]

Solid

Magnesium carbonate CaCO3 Magnesium hydroxide Aluminium hydroxide

Mass of solid to neutralise 20 cm3 of acid 0.7 g 1.2 g 0.6 g 0.4 g

(i) Calculate the costs of each solid used.

.............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [4] (Continued...)

GCSE CHEMISTRY


QUESTIONSHEET 15 CONTINUED (ii) Use all the information given to choose the best antacid. Give a reason for your answer .............................................................................................................................................................................. ..............................................................................................................................................................................

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ma

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e.c

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......................................................................................................................................................................... [3]

TOTAL / 14

GCSE CHEMISTRY


QUESTIONSHEET 16


James spilt some acid on the floor. He looked at the possibility of treating it with one of four chemicals. Their properties are summarised in the table.

(a) (i)

pH 13.0 8.5 8.0 1.0

reaction with acid produces a salt and water produces a salt, water and carbon dioxide produces a salt and water no reaction

Why would substance D be useless for the purpose?

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substance A B C D

......................................................................................................................................................................... [1]

e.c

(ii) Which other substance would you advise him to avoid? (Give a reason)

..............................................................................................................................................................................

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......................................................................................................................................................................... [2] (iii) What type of substance is B?

......................................................................................................................................................................... [1] Sodium chloride is probably the best known salt. It is used in the food industry, spread on roads in winter and used to make a range of other chemicals. State two uses of sodium chloride in the food industry.

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(i)

ma

(b)

..............................................................................................................................................................................

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......................................................................................................................................................................... [2] (ii) Name two other chemicals made from sodium chloride. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) Why is sodium chloride spread on winter roads? ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY


Low Demand Questions

QUESTIONSHEET 17

Nettles, bees and ants sting by injecting acid into your skin. Wasp stings are alkaline. (a)

How could you test to prove that the liquid from an ant is acid? .............................................................................................................................................................................. ......................................................................................................................................................................... [2] Vinegar is used to treat a wasp sting and ammonia to treat a bee sting. Explain why this works and what it tells you about vinegar and ammonia.

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(b)

..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [3]

ctiv

Car batteries contain strong sulphuric acid. To treat a spillage from a car battery, you must first add lots of water then put washing soda on it. Explain this treatment.

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

......................................................................................................................................................................... [2]

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(c)

TOTAL / 7

GCSE CHEMISTRY



QUESTIONSHEET 18

The pH of soil is very important in deciding which crops grow best. The table below shows the pH ranges which are best for some plants. pH range 6.0 to 7.5 5.0 to 6.5 6.0 to 7.0 6.0 to 8.0

The soil in three fields was tested. The results are shown below.

In which field is the soil most acidic?

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(a)

pH of soil 6.6 7.3 5.5

e.c

field A B C

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Plant beans potato onion leek

......................................................................................................................................................................... [1] (b)

For each field list the crops which would grow best in it.

ma

Field A ................................................................................................................................................. [3] Field B .................................................................................................................................................. [2]

Lime can be added to raise the pH of the soil. Which field would need lime before you could grow leeks in it?

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(c)

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Field C .................................................................................................................................................. [1]

......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 19

Epsom salts was a favourite medicine of our grandparents. Its chemical name is magnesium sulphate. (a)

Write down the formula of magnesium sulphate. ......................................................................................................................................................................... [1]

For each of the methods above, give the correct chemical name of two substances which could be mixed to make magnesium sulphate.

e.c

(b)

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Salts can be made in a number of ways. I adding a metal to an acid II adding a carbonate to an acid III adding a hydroxide to an acid

method I ............................................................................................................................................... [2]

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method II ............................................................................................................................................... [2] method III ............................................................................................................................................. [2]

ma

In each case the magnesium sulphate is formed as a solution in water. What would you need to do to produce solid magnesium sulphate?

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......................................................................................................................................................................... [1]

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(c)

TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 20

Complete the following sentences about acids, bases and salts. Acids have a pH below ________.

[1]

(ii)

When acids are mixed with alkalis they become ________.

[1]

(iii)

All acids contain ________.

[1]

(iv)

Acids react with carbonates to produce ________ ________ gas.

[1]

(v)

The acid found in vinegar is called ________ ________.

(vi)

Acids are also found in __________.

e.c

(vii) An example of an alkali is _________.

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(i)

[1] [1] [1]

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ma

ctiv

(viii) Safety spectacles must be used when handling acids or alkalis, because they are ________.

[1]

TOTAL / 8

GCSE CHEMISTRY

ATOMIC STRUCTURE & BONDING


QUESTIONSHEET 1

(a)

Oxygen and sulphur are in the same group of the periodic table. Complete the table below to show the arrangement of electrons in oxygen and sulphur atoms.

shell 1

shell 2

shell 3

[2]

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Atom oxygen sulphur

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e.c

(b) (i) Draw a diagram of an oxygen atom.

[2]

(ii) Use your diagram to describe two ways in which oxygen can achieve a full outside shell of electrons.

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

Some of the oxygen in the atmosphere is in the form of ozone, O3. Scientists believe that chlorine radicals are destroying ozone.

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(c)

he

......................................................................................................................................................................... [2]

(i) What is the difference between a chlorine radical and a chlorine molecule? .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) What substances are thought to be main sources of chlorine radicals in the atmosphere? ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 2

(a)

There are eleven electrons in a sodium atom. The amounts of energy required to remove each one have been measured and the results shown on a sketch graph. 180000 160000 140000 120000

Energy /kJmol-1 100000

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80000 60000 40000

0

1

2

3

4

5

6

7

e.c

20000 8

9

10

11

(i)

ctiv

Number of electrons

Why is the first electron in sodium the easiest to remove?

..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (ii) Why do the energies for electrons 2 to 9 go up by relatively small amounts?

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......................................................................................................................................................................... [1] (iii) Why are the last two energies very high?

(b)

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......................................................................................................................................................................... [1]

Draw a sketch graph to show the energies needed to remove the first four electrons in aluminium. Explain your answer.

.............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 7

GCSE CHEMISTRY



QUESTIONSHEET 3

(a) (i)

Explain what is meant by the numbers in the symbol

40 20

Ca .

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Use the numbers to state the number of protons, neutrons and electrons found in

Ca

electrons

[3]

ion H+

protons

127 53

79 34

I−

Se 2 −

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Fe 3+

electrons

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Be 2 +

56 26

neutrons

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1 1

9 4

e.c

Complete the table below to show the numbers of protons, neutrons and electrons found in the ions shown.

[8]

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(b)

neutrons

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protons

40 20

TOTAL / 13

GCSE CHEMISTRY



QUESTIONSHEET 4

Neon has two main isotopes,

Ne and

22 10

Ne

Draw diagrams of the atoms of each of the neon isotopes.

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(a)

20 10

[3]

e.c

(b) Neon gas is made up of 90% of neon-20 and 10% of neon-22. Calculate the exact relative atomic mass of neon.

..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [3] (c) How do the chemical properties of each isotope of neon compare with each other? Explain your answer.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

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.............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 5

(a) (i)

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The diagram below shows the electronic arrangement of an unknown substance.

How many protons would there be if the unknown substance was a neutral atom?

e.c

......................................................................................................................................................................... [1] (ii) What would the diagram represent if it was a neutral atom?

ctiv

......................................................................................................................................................................... [1] (b)(i) How many protons would there be if the substance was a 2+ ion?

ma

......................................................................................................................................................................... [1] (ii) What would the diagram represent if it was a 2+ ion?

(c) (i)

he

......................................................................................................................................................................... [1] In what group of the periodic table would the unknown substance be if the represented a 1+ ion?

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......................................................................................................................................................................... [1] (ii) How many neutrons would the 1+ ion have if its relative atomic mass was 39? ......................................................................................................................................................................... [1] (d) (i)

In what group of the periodic table would the unknown substance be if it represented a 1- ion?

......................................................................................................................................................................... [1] (ii) What would the relative atomic mass of the 1- ion be if it had 20 neutrons? ......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 6

An unknown element is found to exist as the following two isotopes: 24 13

X

Complete the following table: number of protons

(b)

X

28 13

X

number of electrons 13

om

24 13

number of neutrons

15

13

Describe what is meant by the term ‘isotopes’.

[2]

e.c

(a)

28 13

X

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

(c)

ma

......................................................................................................................................................................... [2] In experiments, both isotopes were found to show the same chemical behaviour. Use the information in the table to explain why the chemical behaviour of both isotopes is the same.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

(d)

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......................................................................................................................................................................... [2] A naturally occurring sample was found to contain 25% of X-24 and 75% of X-28. Calculate the relative atomic mass of the element X. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] (e)

Use your periodic table to identify X. ......................................................................................................................................................................... [1]

TOTAL / 9 High Demand Questions

QUESTIONSHEET 7

GCSE CHEMISTRY


B

C

D

E

F

e.c

A

om

The diagrams below represent the electronic arrangement of different atoms and ions.

Which letter represents an atom of a Group I metal?

ctiv

(a)

......................................................................................................................................................................... [1] (b)

Which letter represents an atom of a Group VII non-metal?

ma

......................................................................................................................................................................... [1]

(c)

Which letter represents an atom of a noble or inert gas?

he

......................................................................................................................................................................... [1] Which letter represents an atom which is not in the second period of the Periodic Table?

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(d)

......................................................................................................................................................................... [1] (e)

Which letter represents an ion of a Group I metal? ......................................................................................................................................................................... [1]

(f)

Which two letters represent atoms which form an ionic compound with a formula similar to Na2S? ......................................................................................................................................................................... [1]

(g)

Which two letters represent atoms which form a molecule with a formula similar to SiCl4?

......................................................................................................................................................................... [1]

TOTAL / 7 High Demand Questions

QUESTIONSHEET 8

GCSE CHEMISTRY

(a)


Use the Periodic Table to write down the electronic arrangement of: (i) calcium ......................................................................................................................................................................... [1] (ii) chlorine ......................................................................................................................................................................... [1] If calcium is heated and put into a gas jar of chlorine a violent reaction takes place and solid calcium chloride is formed. The reaction proceeds due to the transfer of electrons. Use the electron arrangements and the idea of electron transfer to explain how the reaction between atoms of calcium and chlorine takes place. (You may include a diagram in your answer)

ctiv

e.c

(i)

om

(b)

..............................................................................................................................................................................

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

(ii)

he

......................................................................................................................................................................... [4] Write down the formulae of the ions that calcium and chlorine form during the reaction.

(iii)

ww w.c

......................................................................................................................................................................... [2] Write down the formula of calcium chloride.

......................................................................................................................................................................... [1] (c)

Calcium chloride is a solid at room temperature and has a high melting point. Explain why calcium chloride has a high melting point. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 11 Medium Demand Questions

QUESTIONSHEET 9

GCSE CHEMISTRY


Carbon is known to exist as two different allotropes. The allotropes are known as diamond and graphite. Both diamond and graphite consist of carbon atoms bonded together in three-dimensional structures. Carbon atoms

e.c

om

Carbon atoms

(a)

What is the name given the type of bond in which electrons are shared?

Diamond is one of the hardest substances known to man and is used on the edges of glass cutting tools. Explain why the structure of diamond makes it so hard.

ma

(b) (i)

ctiv

......................................................................................................................................................................... [1]

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

he

(ii) Graphite is soft and slippery and is used to lubricate surfaces. Explain why the structure of graphite makes it soft and slippery.

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.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

Diamond is an electrical insulator, but graphite conducts electricity. Explain why graphite conducts electricity. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]


QUESTIONSHEET 10

GCSE CHEMISTRY


om

Various parts of the helicopter below are made out of metal, because metals are strong and malleable.

Describe, with the aid of a diagram, the metallic bonding present in metals.

ctiv

e.c

(a)

Use your knowledge of the structure of metals to explain why: (i)

they are strong

ma

(b)

[4]

..............................................................................................................................................................................

he

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [2] (ii) they are malleable

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (c)

As the blades of the helicopter rotate, heat produced in the joints is conducted away along the blades. Explain how metals conduct heat. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(d)

The properties of some of the metals used in the helicopter have been altered by mixing them with other metals. What name is given to this type of mixture? ......................................................................................................................................................................... [1]


QUESTIONSHEET 11

GCSE CHEMISTRY


Sodium chloride is often called common salt. It can be made by reacting a small piece of hot sodium with chlorine gas. (a)

Write the electronic arrangement for an atom of:

(i)

sodium

......................................................................................................................................................................... [1] (ii) chlorine

Write down the formulae of the ions formed by: (i)

sodium

e.c

(b)

om

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1]

ctiv

(ii) chlorine

......................................................................................................................................................................... [1] (c)

Write down the formula of sodium chloride.

(d)

ma

......................................................................................................................................................................... [1] Solid sodium chloride will not conduct electricity, but when dissolved in water it will. Explain why an aqueous solution of sodium chloride conducts electricity.

he

(i)

..............................................................................................................................................................................

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......................................................................................................................................................................... [1] (ii) In what other way could you alter the state of sodium chloride so that it will conduct electricity? ......................................................................................................................................................................... [1] (e)

A hot piece of sodium was placed in a jar of helium. No reaction took place. (i)

Write the name of the group of the periodic table to which helium belongs.

......................................................................................................................................................................... [1] (ii) Explain why helium is unreactive. ......................................................................................................................................................................... [1]


QUESTIONSHEET 12

GCSE CHEMISTRY


The following table shows some of the ions found in natural waters. ion

Mg2+

Na+

SO42-

NO3-

Ca2+

C1-

K+

name

magnesium

sodium

sulphate

nitrate

calcium

chloride

potassium

Use the list of ions to work out the formulae of the following compounds: (Explain your answers)

(i)

sodium sulphate

om

(a)

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

e.c

(ii) potassium nitrate

..............................................................................................................................................................................

ctiv

......................................................................................................................................................................... [2] (iii) calcium chloride

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iv) magnesium nitrate

he

..............................................................................................................................................................................

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......................................................................................................................................................................... [2] (v) potassium chloride

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (b) (i)

What type of bonding occurs in all of these compounds?

......................................................................................................................................................................... [1] (ii) Explain how this type of bonding occurs. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(Continued...)

GCSE CHEMISTRY

ATOMIC STRUCTURE & BONDING QUESTIONSHEET 12 CONTINUED

(c) (i)

Iodine is in the same group of the Periodic Table as chlorine. What is the formula of an iodide ion?

......................................................................................................................................................................... [1] (ii) Strontium, Sr, is in the same group of the Periodic Table as magnesium. What is the formula of the strontium ion? ......................................................................................................................................................................... [1]

om

(iii) What is the formula of strontium iodide?

ww w.c

he

ma

ctiv

e.c

......................................................................................................................................................................... [1]

TOTAL / 16

GCSE CHEMISTRY Medium Demand Questions

ATOMIC STRUCTURE & BONDING QUESTIONSHEET 13

The flow chart below can be used to decide on the type of bonding found in different substances. Is the substance a solid?

no

yes

simple molecular

Does it melt at a low temperature?

yes

no Does it conduct electricity when solid?

e.c

no

yes

giant ionic

ctiv

Does it conduct electricity when molten or dissolved in water?

giant metallic

om

yes

no

ma

giant atomic

Use the chart to identify the structure of the following substances: (a) (i)

Decane boils at –30oC. It does not conduct electricity under any circumstances.

he

......................................................................................................................................................................... [1]

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(ii) Boron melts at 2027oC. Molten boron does not conduct electricity. ......................................................................................................................................................................... [1] (iii) Glucose melts at 146oC, but the molten solid does not conduct electricity. ......................................................................................................................................................................... [1] (iv) Solid cobalt conducts electricity. It melts at 1495oC. ......................................................................................................................................................................... [1] (v) A solution of calcium nitrate in water conducts electricity. Solid calcium nitrate melts at 561oC. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY

ATOMIC STRUCTURE & BONDING QUESTIONSHEET 13 CONTINUED

(b)

Carbon dioxide has a simple molecular structure. What does this tell you about its melting point and boiling point? ......................................................................................................................................................................... [1]

[2]

he

ma

ctiv

e.c

om

Draw a diagram to show the structure of cobalt.

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(c)

TOTAL / 8

GCSE CHEMISTRY



The table below shows the electronic arrangements of six atoms, A to F. atom

A

B

C

D

E

F

electronic arrangement

2, 8, 6

2, 8, 8

2, 8, 3

2

2, 8, 8, 6

2, 5

(a)

Two atoms from the same group of the periodic table

om

Use the letters representing the atoms to select the following:

..............................................................................................................................................................................

(b)

e.c

......................................................................................................................................................................... [2] The ion K+

(c)

ctiv

......................................................................................................................................................................... [1] Two noble gases.

..............................................................................................................................................................................

(d)

ma

......................................................................................................................................................................... [2] An atom which has 3 electrons in its outside shell.

(e)

he

......................................................................................................................................................................... [1] An atom which has 5 electrons in its outside shell.

(f)

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......................................................................................................................................................................... [1] An atom with the atomic number 24.

......................................................................................................................................................................... [1] (g)

An atom with 7 protons.

......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



The diagrams below show the structures of ethanol, mica and diamond.

C

C

H

H

O H

O

Si

O

O O

Si O

O

Si

O

O

O O

Si

O

Si

O

O

O Mica

Ethanol

How many bonds does each carbon have in: (i)

ethanol?

Diamond

e.c

(a)

Si

H

om

H

O

O

O H

......................................................................................................................................................................... [1]

ctiv

(ii) diamond?

......................................................................................................................................................................... [1] How many bonds does each hydrogen have in ethanol?

ma

(b)

......................................................................................................................................................................... [1] (c) (i)

How many bonds does each silicon have in mica?

he

......................................................................................................................................................................... [1]

ww w.c

(ii) How many bonds does each oxygen have in mica? ......................................................................................................................................................................... [1] (d) (i)

Which of the elements, carbon, hydrogen, oxygen and silicon would you expect to find in the same group of the Period Table?

......................................................................................................................................................................... [1] (ii) Explain your answer.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY


QUESTIONSHEET 16


(a) The diagram below shows an atom of magnesium.

om

PART A

electron

What is the name of part A?

e.c

(i)

......................................................................................................................................................................... [1]

ctiv

(ii) What two types of particle does part A contain?

..............................................................................................................................................................................

(iii) What is the charge on part A?

ma

......................................................................................................................................................................... [2]

......................................................................................................................................................................... [1]

he

(b)(i) How many electrons are in one atom of magnesium?

......................................................................................................................................................................... [1]

ww w.c

(ii) Write the electron arrangement for an atom of magnesium. ......................................................................................................................................................................... [1] (c) (i)

Use the diagram and your answer to part (b) to answer the following questions. In what group of the Periodic Table is magnesium?

......................................................................................................................................................................... [1] Explain your answer.

......................................................................................................................................................................... [1] (ii) In what period of the Periodic Table is magnesium? ......................................................................................................................................................................... [1] Explain your answer. ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 17

Oxygen is able to form two bonds with other elements. Potassium can form one bond, magnesium two and aluminium three. (a)

Work out the formulae of the following compounds. (i)

potassium oxide

om

......................................................................................................................................................................... [1] (ii) magnesium oxide ......................................................................................................................................................................... [1] (iii) aluminium oxide

(b)

e.c

......................................................................................................................................................................... [1] Iron sometimes forms two bonds and sometimes three. Work out the formulae of the two oxides of iron.

ctiv

(i)

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

(ii) How are the two oxides of iron distinguished in their names?

..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [1]

TOTAL / 6

GCSE CHEMISTRY



QUESTIONSHEET 18

Here are the formulae of three compounds containing sodium. (i) NaCl

(a)

(ii) Na2SO4

(iii) NaHCO3

Give the name of each compound. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [3] Which compound is made up of the most atoms?

e.c

(b) (i)

......................................................................................................................................................................... [1]

ctiv

(ii) How many atoms does it contain?

......................................................................................................................................................................... [1] (c)(i)

Which compound has the most different types of atoms?

ma

......................................................................................................................................................................... [1] (ii) List the types of atom in this compound.

he

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [3]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 19

Complete the following paragraphs about atoms. Atoms are the ________ particles of matter that can exist on their own. They are made up of particles called protons, ________ and electrons. Protons have a ________ charge and electrons have a _________ charge. The protons are found in the _______ of the atom. In a neutral atom, the number of protons must _________

om

the number of electrons. If they do not, the particle will be called an _______. The number of protons in an atom is called its ________ ________. The total number of particles in the nucleus gives the ________ ________ of the element.

e.c

The atoms of different elements are _________. They must contain different numbers of ________ and

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he

ma

ctiv

________, although they may have the same number of ________.

TOTAL / 13

GCSE CHEMISTRY



QUESTIONSHEET 20

Complete the following table

neon

symbol mass number

20

atomic number

10

carbon

Mg

N

24

14 11

12

12

7

6

7

6

[9]

ww w.c

he

ma

ctiv

e.c

number of neutrons

sodium

om

Name of element

TOTAL / 10

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 1

A gas barbecue uses butane (C4H10) as a fuel. The butane is stored as a liquid in a container. When the burner is turned on, the liquid turns to a gas and is lit by pushing a button to create a small spark. (a)

Suggest one advantage and one disadvantage of using butane compared to charcoal as a source of heat. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(i)

Describe the arrangement and movement of molecules in butane when it is:

om

(b)

a liquid

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ctiv

(ii) a gas

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] What term is used to describe the change of state from liquid to gas?

ma

(c)

......................................................................................................................................................................... [1]

(ii)

ww w.c

he

(d)(i) Draw a diagram to show the structural arrangement of the atoms in a molecule of butane.

[2]

How does the structure of butane explain why it has a low boiling point?

......................................................................................................................................................................... [1] (e)

Explain why a spark is needed to start the butane burning. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 12

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 2

Fuel cells are often taken into space to supply energy. They turn the energy of a fuel directly into electricity. steam

-

hot potassium hydroxide solution

(a) (i)

ctiv

FUEL CELL

om

porous carbon containing nickel

oxygen

e.c

hydrogen

+

Why are porous electrodes needed in a fuel cell?

..............................................................................................................................................................................

ma

......................................................................................................................................................................... [1] (ii) Why is nickel included in the electrodes?

(b)

he

......................................................................................................................................................................... [1] What is the main way in which fuel cells differ from other electrochemical cells?

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (c)

Write an equation for the overall reaction taking place in a fuel cell. ......................................................................................................................................................................... [2]

(d)

Give two reasons why fuel cells are more suitable than dry cells for use in spacecrafts. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(e)

What other type of cell could be used in a spacecraft? ......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 3

A bomb calorimeter is used to burn small, weighed samples of fuels in an atmosphere of oxygen. The energy produced is transferred to the surrounding water. The fuels are electrically ignited. A bomb calorimeter is often used to find the energy values of foods.

om

thermometer

stirrer

water fuel

BOMB CALORIMETER

(a) (i)

e.c

oxygen

What is the advantage of burning the fuel in oxygen rather than in air?

ctiv

......................................................................................................................................................................... [1] (ii) What is the advantage of surrounding the bomb calorimeter with water?

A bomb calorimeter was used to measure the energy value of glucose. When 2 g of glucose was burned, 31 200 J of energy were released. (i)

Complete the equation for the combustion of glucose. C6H12O6

+

6O2

∏

he

(b)

ma

......................................................................................................................................................................... [1]

+

[2]

ww w.c

(ii) Calculate the energy value of glucose in kJ per 100 g. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 6

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 4

(a)

Cold packs are used to treat sports injuries. A pack contains water and ammonium nitrate crystals. When mixed, rapid cooling takes place. Draw an energy level diagram to show the process occurring in the cold pack. Explain your diagram.

e.c

om

(i)

[3]

ctiv

(ii) Explain in terms of bonding why this process takes in heat.

.............................................................................................................................................................................. ..............................................................................................................................................................................

A company has recently invented ‘cook-in-the-box’ meals. To start the cooking process a tab is pulled which lights a match. The match starts a reaction which continues without further heating.

he

(b)

ma

......................................................................................................................................................................... [3]

(i)

ww w.c

A reaction which could be used is that between aluminium and iron(III) oxide, to produce aluminium oxide and iron. Write a symbol equation for the reaction between aluminium and iron(III) oxide.

......................................................................................................................................................................... [2] (ii) Explain why the match is needed to start the reaction, but once started it continues without further heating. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 10

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 5

A Sumo wrestler eats more than 7 kg of steak every day, together with fresh vegetables. An Olympic rower’s lunch would be something like 350 g steak, vegetables, treacle pudding and unsweetened lemon juice. (a) Why does the rower eat treacle pudding, but the sumo wrestler does not? ..............................................................................................................................................................................

om

......................................................................................................................................................................... [2] (b) In view of your answer to (a), why is the rower’s lemon juice unsweetened?

..............................................................................................................................................................................

ww w.c

he

ma

ctiv

e.c

......................................................................................................................................................................... [2]

TOTAL / 4

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 6

When hydrogen reacts with iodine, we can show the reaction as follows: H – H + I – I Æ 2 (H – I) (a)

Given the following bond energies, calculate the heat of reaction. (H – H = 436 kJ,

I – I = 151 kJ,

H – I = 298kJ)

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

(b)

Is the reaction exothermic or endothermic?

e.c

......................................................................................................................................................................... [3]

......................................................................................................................................................................... [1]

he

ma

ctiv

Draw an energy level diagram for the reaction.

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(c)

[3]

TOTAL / 7

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 7

When 10 cm3 of 0.1M hydrochloric acid reacts with 10 cm3 of 0.1M sodium hydroxide solution, the temperature rises from 20°C to 35°C. (a)

Use the formula heat energy = 4.2 5 temperature change 5 mass of reactants (in grams) to calculate the energy in kilojoules from the reaction. The density of both dilute hydrochloric acid and sodium hydroxide is 1g/cm3.

om

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] How many moles of 0.1M hydrochloric acid are in 10 cm3 of 0.1 M solution?

e.c

(b)

..............................................................................................................................................................................

(c)

ctiv

......................................................................................................................................................................... [2] Write a symbol equation for the reaction between hydrochloric acid and sodium hydroxide.

How much energy would you get by reacting 1 mole of hydrochloric acid?

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

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(d)

ma

......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 8

The reactions between bromine (Br2) and hydrogen (H2) to make hydrogen bromine (HBr) can be represented by the following equation: Br-Br + H-H (a)

∏

H-Br +H-Br

Use the following bond energies to answer questions (i), (ii) and (iii). Br-Br: 193 kJ/mol; H-H: 436 kJ/mol; H-Br: 366 kJ/mol Calculate the total energy required to break bonds in this reaction.

om

(i)

.............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

Answer ............................................................................................................................................ kJ/mol [2] (ii) Calculate the total energy released when bonds are formed in this reaction.

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

Answer ............................................................................................................................................ kJ/mol [2] (iii) Calculate the overall energy change for this reaction.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

(b)

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Answer ............................................................................................................................................ kJ/mol [2] Explain what the sign of the answer you calculated in (a) part (iii) tells you about the reaction. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (c)

Below is the energy level diagram for the reaction between hydrogen and bromine. a

energy

b c d

reaction path

Write down the letter which represents the activation energy ......................................................................................................................................................................... [1] TOTAL / 8

GCSE CHEMISTRY

ENERGETICS QUESTIONSHEET 9


Lucy was trying to compare the amount of energy released when three different alcohols were burned. She used the apparatus shown below. beaker

water

Lucy weighed the burner before and after burning the alcohols. She stirred the water throughout. (i)

Explain why she weighed the burner before and after.

e.c

(a)

om

alcohol

burner

......................................................................................................................................................................... [1]

ctiv

(ii) Why did Lucy stir the water?

......................................................................................................................................................................... [1] (iii) What else would Lucy need to measure before and after burning the alcohol?

ma

......................................................................................................................................................................... [1] (iv) What two things would Lucy need to keep the same if she was to make a fair comparison between the alcohols?

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Lucy calculated the temperature rise for each gram of alcohol which was burned.

ww w.c

(b)

(i)

alcohol

temperature rise

mass burned

temperature rise per gram burned

methanol

16oC

2g

8oC/g

ethanol

33oC

3g

11oC/g

propanol

48oC

4g

Complete the table.

[1]

(ii) Which alcohol releases the most energy per gram? Suggest an explanation. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] TOTAL / 9

GCSE CHEMISTRY



When a small piece of calcium is added to water in a beaker a reaction occurs. (a)

What would you observe? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(i)

om

50 cm3 of water was heated from 20°C to 25°C in the reaction. (heat energy = 4.2 × temperature change × mass of water in grams)

(b)

Calculate the energy given off.

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ctiv

(ii) Is the reaction exothermic or endothermic?

......................................................................................................................................................................... [1] Write the equation (symbols) for the reaction between calcium and water.

he

ma

......................................................................................................................................................................... [2]

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(c)

TOTAL / 7

GCSE CHEMISTRY



When the fuel methane is burnt in a Bunsen burner heat energy is released to the surroundings. The amount of heat given out from the Bunsen burner is controlled by the position of the air hole. (i)

Is the flame of a Bunsen burner hottest when the air hole is closed or open?

......................................................................................................................................................................... [1] (ii) Explain your answer to part (i).

(b)

om

......................................................................................................................................................................... [1] Methane is a part of a group of chemicals called hydrocarbons. Which two elements do hydrocarbons contain?

e.c

(i)

1. ................................................................................................................................................................

ctiv

2. ................................................................................................................................................................ [2] (ii) When any hydrocarbon burns which two chemical compounds are formed? 1. ................................................................................................................................................................

(i)

Explain what is meant by the term ‘activation energy’.

he

(c)

ma

2. ................................................................................................................................................................ [2] The methane does not burn until it is lit by a naked flame. The energy supplied by the flame is called activation energy.

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [2] (ii) The rate of some chemical reactions can be increased by using a catalyst. Use the idea of activation energy to explain how a catalyst works. .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



The following experiment was used to compare how much heat energy three different fuels gave out when they were burnt. thermometer metal can

100 g water

(i)

temperature of water at start 19oC 20oC 18oC

Are the reactions exothermic or endothermic?

e.c

fuel ethanol paraffin white spirit

om

Here are the results when 1.0 g of each fuel was burnt.

temperature of water at end 36oC 47oC 41oC

ctiv

(a)

spirit burner

.............................................................................................................................................................................. Explain your answer.

ma

......................................................................................................................................................................... [2] (ii) What was the temperature change when 1.0 g of ethanol was burnt?

he

......................................................................................................................................................................... [1] (iii) Which fuel released the most energy when it was burnt?

ww w.c

......................................................................................................................................................................... [1] (iv) Why it is important to burn 1.0 g of each fuel in each experiment? ......................................................................................................................................................................... [1] (b)

When fuels burn they react with a gas in the air. Write down the name of this gas. ......................................................................................................................................................................... [1]

(c)

When ethanol burns in excess air, carbon dioxide is released into the atmosphere. Describe one problem that this may cause in the environment. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(d)

When ethanol burns in a shortage of air another gas is formed which is highly toxic. Write down the name of this toxic gas. ......................................................................................................................................................................... [1] TOTAL / 9

GCSE CHEMISTRY



Look at the diagram. It shows the apparatus used to calculate the energy released when fuel is burnt. thermometer metal can

100 g water

om

spirit burner

(a)

temperature of water at start 20oC 19oC 21oC

temperature of water at end 40oC 58oC 42oC

ctiv

fuel ethanol paraffin petrol

e.c

The table below shows the results when 1.0 g of each fuel is burnt.

Which fuel released the least amount of heat energy?

Explain your answer

ma

..............................................................................................................................................................................

(b)

he

......................................................................................................................................................................... [2] Why is it important for there to be 100 g of water in the metal can for each reaction?

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

Calculate the energy transferred when 2.0 g of paraffin burns. (The specific heat capacity of water is 4.2 J g-1 K-1) .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 7

GCSE CHEMISTRY



The following diagram represents the energy level diagram for the reaction between magnesium (Mg) and oxygen (O2) to form magnesium oxide (MgO).

om

energy

reaction path

On the energy level diagram write the words reactants and products in the correct places.

(b)

Indicate on the energy level diagram the activation energy.

(c)

The reaction between magnesium and oxygen may be represented by the following symbol equation:

[1]

e.c

(a)

ctiv

[1]

2Mg + O2 → 2MgO

Calculate the mass of magnesium required to produce 100 g of magnesium oxide. (Relative atomic masses: O = 16, Mg = 24)

ma

(i)

..............................................................................................................................................................................

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

(ii)

ww w.c

......................................................................................................................................................................... [3] It is known that 32 g of oxygen takes up 24 dm3 of space at 25oC. Calculate the volume of oxygen that is needed to react completely with 12 g of magnesium. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 8

GCSE CHEMISTRY



In the laboratory a Bunsen burner is used as a heat source. The gas which is burnt in a Bunsen burner is called methane. (i)

When methane is burnt heat energy is released into the surroundings. What name is given to this type of reaction?

......................................................................................................................................................................... [1]

om

(ii) Methane is called a non-renewable fuel. Explain what is meant by a non-renewable fuel. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

e.c

(iii) Name two fuels which are renewable.

1. ........................................................................................................................................................... [1]

ctiv

2. ........................................................................................................................................................... [1] The reaction between methane (CH4) and oxygen (O2) which takes place during burning produces carbon dioxide (CO2) and water (H2O). It may be represented using the following display formulae. H C H

+

O=C=O

H-O-H

+

O=O

H-O-H

Name two different bonds which are broken during the reaction.

ww w.c

(i)

H

he

H

O=O

ma

(b)

1. ........................................................................................................................................................... [1] 2. ........................................................................................................................................................... [1] (ii) Which two bonds are made during the reaction? 1. ........................................................................................................................................................... [1] 2............................................................................................................................................................. [1] (iii)

Calculate the overall energy change for the reaction between methane and oxygen. The bond energies are C-H: 435 kJ, O=O: 497 kJ, C=O: 803 kJ, H-O: 464 kJ)

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [4]

TOTAL / 13

GCSE CHEMISTRY



The equipment below was used to measure the temperature change when the metal zinc was placed into sulphuric acid. During the reaction heat energy is transferred to the surroundings. thermometer glass beaker sulphuric acid

om

zinc

(a)

What would you see happen to the reading on the thermometer during the experiment?

(b)

e.c

......................................................................................................................................................................... [1] The experiment was repeated but this time a catalyst was also added. Explain what a catalyst is.

ctiv

(i)

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

(ii) What would you see happen to the reading on the thermometer during this second experiment? ..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [2]

TOTAL / 5

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 17

The temperatures of reactions of zinc, magnesium and nickel with hydrochloric acid were measured. The results are shown in the table. Temp at start oC

nickel magnesium zinc

19 19 19

Highest temp reached oC 24 57 30

Temp change o C 5 11

What piece of equipment would you use to measure the temperature?

om

(a)(i)

metal

......................................................................................................................................................................... [1]

e.c

(ii) Calculate the temperature change for the magnesium reaction.

......................................................................................................................................................................... [1]

ctiv

(iii) Calcium is more reactive than zinc.

Predict the temperature change for a reaction between calcium and hydrochloric acid. ......................................................................................................................................................................... [1] What name is given to reactions which give out heat?

ma

(b)

......................................................................................................................................................................... [1] Suggest another reaction which would give out heat.

he

(c) (i)

......................................................................................................................................................................... [1]

ww w.c

(ii) Why are reactions which give out heat useful? ......................................................................................................................................................................... [1] (iii) Why are reactions which take in heat useful? ......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 18

A person’s daily energy requirements depend on a number of things. These include the person’s sex and size. (a)

Name two more things which could affect your energy requirements. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

bowl of cereal bacon egg tea (with sugar)

om

For breakfast a man eats the following 325 J 1430 J 660 J 200 J

e.c

(b)

How much energy in total does he get from his breakfast?

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] An Indian farmer consumes 7200 J per day. The man described above consumes 20 000 J per day.

(i)

ma

(c)

How would you expect the man and the farmer to differ in appearance?

..............................................................................................................................................................................

he

......................................................................................................................................................................... [2]

ww w.c

(ii) Why is the farmer often very tired?

......................................................................................................................................................................... [1] (iii) Suggest two things that the man could do to lose weight. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 19

A modern power station uses powdered coal. A blast of air is passed up through the burning coal. This is more efficient and produces less harmful gases than large pieces of coal. (a)

Why does powdered coal burn more efficiently? ..............................................................................................................................................................................

(b)

Sometimes the powdered coal is blown into a flame. Why is this better?

om

......................................................................................................................................................................... [2]

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Using oxygen instead of air speeds up the burning process. Explain the reason for this.

ctiv

(c)

..............................................................................................................................................................................

(d)

ma

......................................................................................................................................................................... [2] Name two gases which may form when coal is burned.

..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY

ENERGETICS


QUESTIONSHEET 20

(a)

List three characteristics of an ideal fuel. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

om

(b)(i) Describe an experiment to compare paraffin and alcohol as fuels. Mention all the measurements you would make. ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ctiv

......................................................................................................................................................................... [4] (ii) Why would it be difficult to compare coal using the same method? ......................................................................................................................................................................... [1]

ma

(iii) Why is it difficult to compare methane gas using the same method? ......................................................................................................................................................................... [1]

Fuel A produces 1500 kJ Fuel B produces 790 kJ

he

George compared two fuels and came up with the following results.

ww w.c

(c)

Why are these results of very little use?

......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY

INDUSTRIAL PROCESSES


QUESTIONSHEET 1

Since 1900 it has been known that substances containing nitrogen increase the yield of crops. European countries imported large quantities of sodium nitrate (NaNO3) from Chile. This nitrate was a non-renewable resource. (a)

Name the group of chemicals that plants make from nitrate fertilisers. ......................................................................................................................................................................... [1] What is meant by the term ‘non-renewable’.

om

(b)

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] Calculate the relative molecular mass of sodium nitrate. The relative atomic masses of N = 14, O = 16, and Na = 23.

e.c

(c)(i)

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (ii) Calculate the percentage of nitrogen in sodium nitrate.

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

Today nitrate fertilisers are made by first making ammonia gas from nitrogen and hydrogen. (i)

Name the raw material used as a source of nitrogen.

ww w.c

(d)

he

......................................................................................................................................................................... [2]

......................................................................................................................................................................... [1] (ii) Name a raw material used as a source of hydrogen. ......................................................................................................................................................................... [1] (e)

Ammonia is made by passing a mixture of nitrogen and hydrogen over finely divided iron metal. (i)

What is the purpose of the iron?

......................................................................................................................................................................... [1] (ii) Explain why the iron used is finely divided. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(Continued...)

GCSE CHEMISTRY

INDUSTRIAL PROCESSES QUESTIONSHEET 1 CONTINUED

(f)

A solid fertiliser is made by dissolving ammonia gas in water. Ammonia solution is then reacted with an acid. Name the acid you would react with ammonia to make ammonium sulphate. ......................................................................................................................................................................... [1] Overuse of nitrate fertilisers can be harmful. They can cause eutrophication in lakes and rivers. Explain what happens in the eutrophication process.

om

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

ma

ctiv

......................................................................................................................................................................... [4]

ww w.c

(g)

TOTAL / 15

GCSE CHEMISTRY



QUESTIONSHEET 2

National Quicklime is a company that is involved in the quarrying of limestone. They propose to open a new limestone quarry in the Peak District National Park. The proposed site is well known as an area of outstanding natural beauty. (a)

Give three reasons in favour of opening the quarry. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

......................................................................................................................................................................... [3] (b)

Give three reasons against the opening of the quarry.

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] The limestone (calcium carbonate) will be used to make quicklime (calcium oxide). The equation for the reaction is given below:

(i)

CaO(s) +

CO2 (g)

ww w.c

CaCO3(s) →

he

(c)

What do the symbols (s) and (g) mean?

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Calculate the relative molecular masses of calcium carbonate, calcium oxide, and carbon dioxide. (relative atomic masses C=12, O=16, Ca= 40) .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

(Continued...)

GCSE CHEMISTRY


(d)

The company wants to produce 1,680 tonnes of quicklime per week. (i)

Calculate the minimum mass of limestone needed to produce 1,680 tonnes of quicklime.

.............................................................................................................................................................................. ..............................................................................................................................................................................

om

......................................................................................................................................................................... [2] (ii) Suggest a reason why more than the minimum mass you have calculated would have to be heated to obtain 1,680 tonnes of quicklime.

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [1]

ctiv

Give another use of limestone.

he

ma

......................................................................................................................................................................... [1]

ww w.c

(e)

TOTAL / 15

GCSE CHEMISTRY



QUESTIONSHEET 3

Chlorine is manufactured by the electrolysis of sodium chloride solution. A simple electrolysis cell that can be used in the laboratory is shown below.

om

sodium chloride solution

Label the anode on the diagram.

(b)

How would you prove that the gas collected was chlorine?

[1]

e.c

(a)

ctiv

Test

......................................................................................................................................................................... [1] Result

ma

......................................................................................................................................................................... [1] (c)

Give one important use of chlorine.

(d)

he

......................................................................................................................................................................... [1] Complete the ionic equation showing the formation of chlorine gas.

(e)

______ + ______

ww w.c

___ Cl − →

[1]

Name the other gas formed in the electrolysis of salt solution. ......................................................................................................................................................................... [1]

(f)

After running the cell for several minutes, some Universal Indicator was added to the cell. The indicator turned blue. (i)

What does this test show?

......................................................................................................................................................................... [1] (ii) Give the chemical name of the substance formed that turns the indicator blue. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(g)

Some students decided to investigate how changing some of the factors in the experiment would affect the amount of chlorine produced. John made the following prediction: 'more chlorine will be produced if the concentration of sodium chloride solution is increased.' Describe how the students could use this apparatus to test their prediction. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [5]

ma

Suggest two other changes that John could investigate to see if they affected the amount of chlorine produced. .............................................................................................................................................................................. ..............................................................................................................................................................................

he

......................................................................................................................................................................... [2]

ww w.c

(h)

TOTAL / 15

GCSE CHEMISTRY



QUESTIONSHEET 4

Aluminium is obtained from bauxite. Bauxite is purified to form aluminium oxide. (a)

Write down the formulae of the ions present in aluminium oxide. aluminium ion _______________

[2]

Aluminium oxide is mixed with cryolite before being placed in the cell. What is the function of the cryolite?

om

(b)

oxide ion _________________

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] Explain why the electrolyte has to be molten in order to conduct electricity.

e.c

(c)

..............................................................................................................................................................................

A typical cell is shown below.

(i)

+

-

cathode

carbon anode

ww w.c

he

Electrolyte mixture of aluminium oxide and cryolite

ma

(d)

ctiv

......................................................................................................................................................................... [2]

Aluminium ions are attracted to the cathode. Write an equation to show how aluminium ions are changed into atoms.

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (ii) Explain what happens to the oxide ions.

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

(Continued...)

GCSE CHEMISTRY


(e)

Extraction of aluminium from its ore uses electricity. Iron can be extracted from its ore by heating with carbon. Gold is found occuring naturally. Explain why these three metals have such different ways of extracting them. .............................................................................................................................................................................. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

e.c

The graph below shows the production of bauxite ore, purified aluminium oxide and aluminium metal from three different countries.

ctiv

20

15

5

Australia

he

ma

10

Jamaica

ww w.c

(f)

bauxite ore

United Kingdom

purified aluminium oxide

aluminium metal

(i) Which country has no deposits of bauxite? ......................................................................................................................................................................... [1] (ii) Suggest two reasons why Jamaica produces little aluminium metal, despite mining large quantities of bauxite. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 14

GCSE CHEMISTRY



QUESTIONSHEET 5

Many power stations burn coal as their source of energy. Coal mainly consists of the element carbon. (a)

Write a symbol equation for the burning of carbon in a good supply of air. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] Coal also contains small amounts of sulphur. The sulphur burns to form sulphur dioxide gas. Explain how sulphur dioxide causes pollution and how this harms trees.

om

(b)

..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [3] One method of preventing this pollution is to remove sulphur dioxide gas before it escapes into the air. This can be done by reacting the gas with calcium oxide in the power station chimney.

ma

(c)

The equation for the reaction is shown below: CaO + SO2

Give the name used to describe this type of reaction.

he

(i)

Æ CaSO3

ww w.c

......................................................................................................................................................................... [1] (ii) Calculate the relative molecular masses of: CaO SO2

[1] [1]

(Relative atomic masses: O = 16, S = 32, Ca = 40) (iii) A power station produces 32 tonnes of sulphur dioxide in one day. Calculate the minimum mass of calcium oxide needed to absorb 32 tonnes of sulphur dioxide. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(Continued...)

GCSE CHEMISTRY


(iv) Give two reasons why a greater mass of calcium oxide would be needed in practice. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

2SO2 (i)

+

O2

om

Another method is to remove the sulphur from coal before it is burnt. The sulphur may be used in the contact process. Sulphur dioxide reacts with oxygen as shown in the equation below: 2SO3

What does the symbol

mean?

e.c

(d)

......................................................................................................................................................................... [1]

ctiv

(ii) Name the product formed in this reaction.

......................................................................................................................................................................... [1] (iii) Name the major chemical formed in the contact process.

ww w.c

he

ma

......................................................................................................................................................................... [1]

TOTAL / 14

GCSE CHEMISTRY



QUESTIONSHEET 6

(a)

Sulphuric acid is made from sulphur by the contact process. Sulphur is burned to form sulphur dioxide. This is then changed to sulphur trioxide by reacting it with more oxygen. A catalyst is used in this stage of the process. 2SO2 + O2

Æ

2SO3

energy released = -189 kJ

The reverse reaction is 2SO3 Æ

2SO2

+

O2

om

What is the energy change for this reaction? ......................................................................................................................................................................... [1] A catalyst is used because it lowers the activation energy. (i)

e.c

(b)

What is meant by activation energy?

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] [1]

ma

(ii) Label the activation energy on the energy level diagram for the formation of sulphur trioxide.

ww w.c

Energy

he

2SO2 + O2

2SO3

Time

(iii)

What effect does a catalyst have by lowering the activation energy?

.............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(c)

The percentage conversion of sulphur dioxide varies with the temperature. This is shown in the graph below: 100

60

e.c

% conversion of SO2 to SO3

om

80

ctiv

40

400

500

600

700

800

he

0 300

ma

20

Temperature / oC

Use the graph to find the percentage of sulphur trioxide produced at a temperature of 575oC.

ww w.c

(i)

......................................................................................................................................................................... [1] (ii) Calculate the amount of sulphur dioxide converted when 300 tonnes of sulphur dioxide ar reacted with oxygen at 575oC. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) Running the process at 300 oC has the advantage of 100% conversion. Suggest one disadvantage of operating at this temperature. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (Continued...)

GCSE CHEMISTRY


(d)

Sulphur trioxide is mixed with concentrated sulphuric acid to form oleum, H2S2O7. The oleum is diluted to produce more sulphuric acid. (i) Give the symbol equation for this reaction. ..............................................................................................................................................................................

om

......................................................................................................................................................................... [2]

(ii) Explain why the oleum is not added directly to water to form sulphuric acid. ......................................................................................................................................................................... [1] The catalyst used contains vanadium. (i)

e.c

(e)

Name the block of the Periodic Table to which vanadium belongs.

ctiv

......................................................................................................................................................................... [1] (ii) Vanadium is a very expensive metal. Explain why, despite the high cost, it can be used in this process.

ma

..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [1]

TOTAL / 13

GCSE CHEMISTRY



QUESTIONSHEET 7

The world produces close to 10 million tonnes of copper each year. Copper pyrites is one of the main ores of copper. The ore contains the elements copper and sulphur. To extract the copper the ore is crushed and concentrated. The concentrated ore is roasted in air to separate the copper from the sulphur. The sulphur reacts with air to form sulphur dioxide gas. (a)

Explain why the ore needs to be concentrated.

(b)

om

......................................................................................................................................................................... [1] Explain why it is important that the sulphur dioxide gas is not allowed to escape into the atmosphere.

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

(c)

ctiv

......................................................................................................................................................................... [2] Sulphur dioxide may be used to make sulphuric acid. Outline the major stages in this industrial process.

ma

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

he

..............................................................................................................................................................................

(d)

ww w.c

......................................................................................................................................................................... [3] The copper formed is called blister copper and is impure. Copper is purified by electrolysis. A diagram of the process is shown below. CATHODE

-

copper

+

ANODE

blister copper

copper sulphate solution

‘anode slime’

(Continued...)

GCSE CHEMISTRY


(i)

Use the diagram to explain how the impure copper is purified.

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [3] Complete the symbol equation for the reaction at the cathode. Cu2+ +

______ →

Cu

e.c

(ii)

[1]

ctiv

(iii) The reaction at the cathode is an example of 'reduction'. Explain this term by using this reaction as an example.

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (iv) What is the importance of the 'anode slime' in paying for this expensive process.

In the periodic table copper is a transition element. It is used in wiring as it is a good conductor of electricity. Give two other properties of transition elements.

ww w.c

(e)

he

......................................................................................................................................................................... [1]

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 15

GCSE CHEMISTRY



QUESTIONSHEET 8

(a) The table below shows the percentage and the boiling point of the three main elements in liquid air. Element argon nitrogen oxygen

Boiling point (oC) -186 -196 -183

Percentage 78.04 % 20.93%

Complete the table.

[1]

(ii)

Name the gas with the highest boiling point ............................................................................... [1]

om

(i)

(b) The following diagram shows the fractionating column for separating liquid air into argon, nitrogen and oxygen.

e.c

well insulated fractionating column

ctiv

nitrogen

A

B

he

perforated shelves

ma

liquid air at 200 oC

(i) Name this method of separation .............................................................................................................. [1]

ww w.c

(ii) Name A. ................................................................................................................................................... [1] (iii) Name B. ................................................................................................................................................... [1] (c) Name two gases which are present in the atmosphere but not in liquid air. ........................................................... and ........................................................ (d) Give one use of (i) argon

[2]

......................................................................................................................................................................... [1] (ii) nitrogen ......................................................................................................................................................................... [1] (e) Explain how oxygen is used in the steel industry. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 11

GCSE CHEMISTRY



QUESTIONSHEET 9

The diagram below shows part of the process in which nitric acid is formed from ammonia.

oxygen

(a)

∧ ∧

hot platinum gauze

∧

+ oxygen

nitrogen monoxide

gases cooled using water

Which raw material is used to obtain oxygen?

nitrogen dioxide

om

ammonia

......................................................................................................................................................................... [1]

(i)

nitrogen monoxide

(ii) oxygen

________________

(iii) nitrogen dioxide

________________

Name the catalyst used in this process.

[3]

ma

(c)

________________

e.c

Write down the formulas for the following substances:

ctiv

(b)

......................................................................................................................................................................... [1] What information given in the diagram suggests that nitrogen monoxide is insoluble in water?

he

(d)

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [1] (e)

Explain how nitrogen dioxide is converted into nitric acid. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(f)

The nitric acid formed may be used to make ammonium nitrate fertiliser. (i)

What substance is added to nitric acid to form ammonium nitrate?

......................................................................................................................................................................... [1] (ii)

What type of reaction takes place when ammonium nitrate is formed?

......................................................................................................................................................................... [1] (Continued...)

GCSE CHEMISTRY


(iii) Explain why nitrate fertilisers are used. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

om

(iv) A bag of garden fertiliser has the label 'N:P:K 10:0:5’ Explain what this information means. ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

he

ma

ctiv

......................................................................................................................................................................... [3]

TOTAL / 15

GCSE CHEMISTRY

INDUSTRIAL PROCESSES QUESTIONSHEET 10


The Haber process is used to manufacture ammonia. Nitrogen gas and hydrogen gas react with each other in the presence of a catalyst. (a)

Name the catalyst used in the Haber process. ......................................................................................................................................................................... [1] Balance the following equation for the reaction N2

(c)

+

____ H2

____ NH3

[2]

This is a reversible reaction. Explain what is meant by the term ‘reversible reaction’.

om

(b)

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] The graph below shows the percentage yield of ammonia at different temperatures and pressures.

ctiv

(d)

ma

100

60

40

20

ww w.c

% yield of ammonia

300o C

he

80

100

200

500o C

300

400

500

pressure/atmosphere

(Continued...)

GCSE CHEMISTRY


(i)

Use the graph to complete the following sentences: The percentage of ammonia __________ as the pressure increases. The percentage of ammonia __________ as the temperature increases.

[2]

(ii) Use the graph to find the conditions required to give a yield of 60% ammonia. pressure __________ atmospheres

[1]

om

temperature __________oC

(iii) On the graph draw the line you would expect showing the percentage yield of ammonia for a temperature of 350oC. Pressures greater than 500 atmospheres increase the yield of ammonia. Suggest two reasons why very high pressures of above 500 atm are not used.

e.c

(e)

[1]

..............................................................................................................................................................................

(f)

ctiv

......................................................................................................................................................................... [2] Temperatures lower than 300oC often give a yield of 100% of ammonia. Suggest a reason why very low temperatures of less than 300oC are not used.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] After reacting the gases with the catalyst a mixture of unreacted nitrogen, unreacted hydrogen and ammonia is formed. The boiling points of these three gases are given in the table below.

he

(g)

ww w.c

gas ammonia hydrogen nitrogen

boiling point (oC) -33 -252 -196

Use the information to suggest a method for extracting the ammonia. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (h)

What happens to the nitrogen and hydrogen that leave the process unreacted? .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

TOTAL / 14

GCSE CHEMISTRY



Iron is extracted from its ore in a blast furnace. The raw materials are iron ore, limestone, carbon, and hot air. (a)

Name one ore of iron. ......................................................................................................................................................................... [1]

(b)

The iron ore is reduced using carbon monoxide. Explain how carbon monoxide is formed in the blast furnace.

om

(i)

..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ctiv

(ii) What is meant by the term 'reduced'?

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] The limestone (CaCO3) is heated to a high temperature and it decomposes. (i)

ma

(c)

Write a symbol equation for the decomposition of limestone.

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ww w.c

(ii) Explain the reason for adding limestone to the furnace. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (d)

Name the two liquids that are tapped off from the furnace. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(e)

The furnace runs for 24 hours a day. Suggest one problem caused by these operating conditions. .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(f)

Discuss the factors that would influence the choice of a site for a new blast furnace. .............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

The iron formed is used to make alloys. Name and give a use of an alloy containing iron.

ctiv

..............................................................................................................................................................................

he

ma

......................................................................................................................................................................... [2]

ww w.c

(g)

e.c

......................................................................................................................................................................... [3]

TOTAL / 15

GCSE CHEMISTRY



QUESTIONSHEET 12

Aluminium metal is extracted from its ore, bauxite. Impurities such as iron(III) oxide and silicon oxide have to be removed. The purified bauxite is mainly aluminium oxide. Aluminium oxide solid is added to the electrolysis cell. bauxite Æ (4 tonnes)

aluminium oxide (2 tonnes)

Æ

aluminium (1 tonne)

om

The cell requires a current of 100,000 amps and reaches a temperature of 1000oC. In Scotland, aluminium is made near to hydroelectric power plants. (a)

Suggest two reasons why the extraction of aluminium is an expensive process.

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Describe three environmental problems which could be caused by an increase in the demand for products made from aluminium.

ma

(b)

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

..............................................................................................................................................................................

ww w.c

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] (c)

A typical electrolysis cell is shown below:

(i)

Label the following on the diagram: anode, cathode, electrolyte, aluminium metal

+

-

[3] (Continued...)

GCSE CHEMISTRY


(ii) Explain why the carbon anodes have to be replaced. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] The following reactions take place at the electrodes: Al3+ + 3e- Æ 2O2- Æ (i)

O2 +

Al 4e-

om

(d)

Which reaction takes place at the cathode?

e.c

......................................................................................................................................................................... [1]

ctiv

(ii) In a day 320 tonnes of oxygen gas are formed. How much aluminium metal will be formed in this time? (relative atomic masses: O = 16, Al = 27)

..............................................................................................................................................................................

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [3]

TOTAL / 14

GCSE CHEMISTRY



Sulphuric acid, H2SO4 is made by a method called the contact process. A flow diagram for that process is shown in the following diagram. gas G

burnt in air

400-500oC catalyst C

om

sulphur dioxide

sulphur

sulphur trioxide dissolved in concentrated sulphuric acid

Name gas G.

add liquid L

concentrated sulphuric acid

ma

(i)

ctiv

e.c

oleum H2S2O7

......................................................................................................................................................................... [1]

he

(ii) Name catalyst C.

......................................................................................................................................................................... [1]

ww w.c

(iii) Name liquid L.

......................................................................................................................................................................... [1] (iv) Complete the symbol equation for the sulphur burning in air. S (....)

+

.......(g)

ς

SO2 (......)

[2]

(v) Explain the importance of not allowing any of the sulphur dioxide to escape into the atmosphere. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (vi) Name all the elements present in oleum, H2S2O7. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(vii) Sulphur dioxide reacts with water to form sulphuric acid: SO3

+

H2O

ς

H2SO4

Explain why this is never done in the contact process. ..............................................................................................................................................................................

om

......................................................................................................................................................................... [1] (viii) Give one industrial use of sulphuric acid.

e.c

..............................................................................................................................................................................

ww w.c

he

ma

ctiv

......................................................................................................................................................................... [1]

GCSE CHEMISTRY

INDUSTRIAL PROCESSES TOTAL / 9

QUESTIONSHEET 14


Ammonia is manufactured by the Haber process where nitrogen is reacted with hydrogen by passing the mixture over iron at certain conditions. (a)

(i)

Complete and balance the equation ......(g)

(ii)

+

.......H2(g)

...... NH3 (g)

[2]

Explain why the mixture is passed over iron.

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [1]

e.c

(iii) State how heat affects the speed of the reaction between the two reactants - nitrogen and hydrogen. ..............................................................................................................................................................................

ctiv

......................................................................................................................................................................... [1] (b) The graph below shows the effect of temperature and pressure on the yield of ammonia produced during its manufacture

ma

80 70

350oC

60

he

Percentages yield of 50 ammonia 40

ww w.c

30

450oC 550oC

20 10 0

0

100

200

300

400

500

Pressure (in atmospheres)

(i) State what happens to the yield of ammonia when: the pressure increases. ......................................................................................................................................................................... [1] the temperature increases. ......................................................................................................................................................................... [1] (ii) The graph shows the highest yield of ammonia can be obtained by using a pressure of 500 atmospheres. Give one reason why this condition is not normally used in industry. ......................................................................................................................................................................... [1]

GCSE CHEMISTRY

INDUSTRIAL PROCESSES (Continued...)

QUESTIONSHEET 14 CONTINUED (c) One of the main uses of ammonia is to manufacture nitrogenous fertilisers such as ammonium sulphate. Name the substance that is used to neutralise ammonia to make this fertiliser.

ww w.c

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY



The diagram below shows a blast furnace which is used for the extraction of iron from iron ore. raw materials

e.c

om

waste gases

hot air

ctiv

hot air

molten iron

ma

A

he

(a) (i) One of the raw materials fed in at the top of the blast furnace is iron ore , which is mainly iron(III) oxide. Name the other two raw materials. 1. ................................................................

II. ................................................................

[2]

ww w.c

(ii) Name the substance which is formed at A.

......................................................................................................................................................................... [1] (b) One of the main reactions taking place inside the blast furnace is Fe2O3 (i)

+

3CO

→

2Fe

+

3CO2

Name the reducing agent in this equation.

......................................................................................................................................................................... [1] (ii) Calculate the relative molecular mass (Mr) of iron(III) oxide, Fe2O3. Ar (Fe) =56

Ar (O) = 16

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

GCSE CHEMISTRY

INDUSTRIAL PROCESSES (Continued...)

QUESTIONSHEET 15 CONTINUED (iii)

Use the given equation to calculate the mass of iron formed from 320 tonnes of iron(lIl) oxide.

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [2]

GCSE CHEMISTRY



QUESTIONSHEET 16

Aluminium is extracted by the electrolysis of molten aluminium oxide (dissolved in molten cryolite). It is an expensive metal to produce. (a) (i)

Give one reason why aluminium is expensive to make.

......................................................................................................................................................................... [1]

om

(ii) State what is meant by the term electrolysis. ......................................................................................................................................................................... [1] (iii) Explain the reason why aluminium oxide is dissolved in molten cryolite.

e.c

......................................................................................................................................................................... [1] (iv) Explain why the aluminium oxide needs to in the molten state.

ctiv

......................................................................................................................................................................... [1] (v) During electrolysis the aluminium ion (Al3+) is attracted towards the negative electrode. Give both the name and symbol of the ion attracted towards the positive electrode. Symbol. .......................................................

ma

Name. ....................................................

[1]

(b) (i) State and explain one important factor that needs to be considered when an aluminium extraction plant site is chosen.

he

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [2] (ii) Aluminium is a metal that is encouraged to be recycled. Explain why we should recycle as much aluminium as possible. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (c) Aluminium has many different uses. Give one reason why aluminium is chosen to make each of the following items: (i) cooking foil ......................................................................................................................................................................... [1] (ii) electric cables ......................................................................................................................................................................... [1] (iii) window frames ......................................................................................................................................................................... [1]

GCSE CHEMISTRY


QUESTIONSHEET 17


This question is about the extraction of metals. Match the metals to their methods of extraction. Metal Sodium Zinc Copper

Method of extraction Heat sulphide with oxygen Electrolysis Reduction with coke

(ii) Explain how you matched the metals to the methods.

om

(a) (i)

[3]

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ctiv

(iii) What is the main element in coke?

......................................................................................................................................................................... [1]

Titanium (Ti) can be extracted from titanium chloride by heating with sodium. TiCl4

4NaCl

What type of reaction is this?

+

Ti

he

(i)

+ 4Na Æ

ma

(b)

......................................................................................................................................................................... [1]

ww w.c

(ii) What does the reaction tell you about titanium compared to sodium? ......................................................................................................................................................................... [1]

GCSE CHEMISTRY


QUESTIONSHEET 18


The diagram below shows the outline of a Blast Furnace. E

e.c

C

om

D

A

(a)

ctiv

B

Select letters which show:

the place where the air blast goes in ______

ma

(i)

[1] [1]

(iii) the place where the hot gases come out ______

[1]

(iv) the place where the iron comes out ______

[1]

What use is made of the hot waste gases?

ww w.c

(b) (i)

he

(ii) the place where the ore and coke go in ______

......................................................................................................................................................................... [1] (ii) Name two of the waste gases.

......................................................................................................................................................................... [2] (c)

The iron formed in the blast furnace is brittle. What element in the iron causes this? ......................................................................................................................................................................... [1]

GCSE CHEMISTRY


QUESTIONSHEET 19


Ammonia is made from nitrogen and hydrogen. (a)

Why is it difficult to react nitrogen with hydrogen? ......................................................................................................................................................................... [1] The reaction is described as reversible. What does this mean?

om

(b)

......................................................................................................................................................................... [1] The reaction is quite slow. What is added to speed it up?

e.c

(c)

......................................................................................................................................................................... [1] Only about 15% of the nitrogen and hydrogen are converted to ammonia. What happens to the remaining 85%?

ctiv

(d)

..............................................................................................................................................................................

ma

......................................................................................................................................................................... [1] (e)

Ammonia is very soluble in water. In what two ways can you recognise a solution of ammonia?

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Ammonia reacts with nitric acid to make a salt which can be used as a fertiliser. (i)

ww w.c

(f)

Name the salt.

......................................................................................................................................................................... [1] (ii)

Why is it a good fertiliser?

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 20

(a)

A lot of chemicals can be made from common salt. (i)

What is the chemical name for common salt?

......................................................................................................................................................................... [1] (ii) Give two other uses for common salt.

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Sodium hydroxide is made from salt.

(i)

Circle a description in the list below that applies to sodium hydroxide. Strong acid

strong alkali

neutral

e.c

(b)

weak acid

[1]

ctiv

(ii) Name two things made using sodium hydroxide.

weak alkali

..............................................................................................................................................................................

Chlorine can be extracted from salt. (i)

Circle two descriptions in the list below that apply to chlorine. Solid

liquid

gas

reducing agent

[2]

ww w.c

(ii) Give two uses of chlorine.

bleach

he

(c)

ma

......................................................................................................................................................................... [2]

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 10

GCSE CHEMISTRY

METALS & THE REACTIVITY SERIES


QUESTIONSHEET 1

Some students made a simple cell. Two pieces of metal foil were dipped into a beaker containing salt solution as shown in the diagram below. The voltage was measured. meter

Name the piece of apparatus that was used to measure the voltage.

ctiv

(a)

e.c

salt solution

om

metal metal A B

......................................................................................................................................................................... [1] The results are given in the table below:

(b)

ma

METAL A magnesium zinc iron copper

METAL B copper copper copper copper

VOLTAGE OBTAINED/volts 1.6 0.6 0.3 0.0

he

EXPERIMENT 1 2 3 4

What is the pattern between the reactivity of the metal and the voltage obtained?

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [3] (c)

Predict the voltage obtained if aluminium was used as metal A and copper was used as metal B. ......................................................................................................................................................................... [1]

(d)

Predict the voltage obtained if metals A and B were swapped over in experiment 1. ......................................................................................................................................................................... [1]

(e)

When silver was used as metal A voltage of 0.05 volts was obtained. Explain this result. .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(f)

Give one disadvantage of making electrical cells using this method. ......................................................................................................................................................................... [1] TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 2

Metal A

Metal C

Metal D

Place the metals on order of reactivity, starting with the most reactive.

e.c

(a)

Metal B

om

Small pieces of four different metals were placed in identical amounts of hydrochloric acid. The results are shown below.

The four metals used in the experiment were calcium, magnesium, iron and platinum. Use your knowledge of these four metals to identify the metals A, B, C & D.

[3]

ctiv

(b)

[2]

When magnesium meets with hydrochloric acid, it forms magnesium chloride and hydrogen. (i)

Balance the following equation Mg(s) + ___HCl(aq)

Æ

he

(c)

ma

Metal A ..................................................................................................................................................... Metal B ...................................................................................................................................................... Metal C ...................................................................................................................................................... Metal D ......................................................................................................................................................

MgCl2(aq) + H2(g)

[1]

ww w.c

(ii) When magnesium reacts with sulphuric acid it forms magnesium sulphate. If a chloride ion is Cl- and a sulphate ion is SO42-, what is the formula of magnesium sulphate? Explain your answer. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) What salt is formed when magnesium reacts with nitric acid? ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 3

Below is a section of the reactivity series for metals. potassium calcium magnesium zinc lead copper

increasing reactivity

Predict if there will be a reaction when the following chemicals are added together. If you predict a react, write a word equation for it. (i)

zinc and copper sulphate solution

e.c

(a)

om

Use this reactivity series to answer the following questions.

prediction

[2]

ctiv

.............................................................................................................................................................................. equation

ma

.............................................................................................................................................................................. (ii) Calcium and potassium sulphate solution

he

prediction

[1]

..............................................................................................................................................................................

ww w.c

equation

.............................................................................................................................................................................. (iii) Magnesium and zinc sulphate solution prediction

[2]

.............................................................................................................................................................................. equation

.............................................................................................................................................................................. (b)

In a displacement reaction, two metals of different reactivity ‘compete’ for oxygen. In such a reaction, oxidation and reduction occur simultaneously.

(i)

What is meant by reduction?

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (Continued...)

GCSE CHEMISTRY

METALS & THE REACTIVITY SERIES QUESTIONSHEET 3 CONTINUED

(ii) Write a word equation for the reaction between magnesium and copper(II) oxide. ......................................................................................................................................................................... [1] (iii) In the equation, circle the reducing agent.

[1]

(iv) The reaction between magnesium and copper(II) oxide needs to be heated. The heat supplies the activation energy. What is meant by the term ‘activation energy’?

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] In a series of experiments it was found that carbon would react with zinc oxide, but not with magnesium oxide. (i)

e.c

(c)

Write down the name of another metal oxide, which would react with carbon.

ctiv

......................................................................................................................................................................... [1] (ii) Write the name of another metal oxide, which would not react with carbon.

ww w.c

he

ma

......................................................................................................................................................................... [1]

TOTAL / 12

GCSE CHEMISTRY



QUESTIONSHEET 4

A student investigated the different reactivities of a set of metals by placing pieces of each metal in metal nitrate solutions. The table below shows some of the results. aluminium

barium 9

lithium 9

8 8

9

9

9 = reaction observed

8 = no reaction

Use the results given to put the metals in order of reactivity starting with the most reactive.

e.c

(a)

magnesium 9 8

om

solution aluminium nitrate barium nitrate lithium nitrate magnesium nitrate

[2]

Use the reactivity series in (a) to complete the table.

[3]

(c)

It is known that aluminium is more reactive than silver. However, when a piece of aluminium is put in a solution of silver nitrate, no reaction is observed. Explain this result.

ctiv

(b)

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [3]

TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 5

Below is a section of the reactivity series of metals. The non-metal, carbon is also included.


om

magnesium aluminium carbon zinc iron lead

Both aluminium and iron are found in nature as their oxides. The methods of extracting the pure metals depend on their reactivity. Aluminium is extracted by electrolysis from its oxide. (i)

e.c

(a)

What is the name of an aluminium ore consisting of aluminium oxide?

ctiv

......................................................................................................................................................................... [1] (ii) During electrolysis, cryolite is added to molten aluminium oxide. Explain why.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

anode

he

(iii) Write balanced ionic equations for the reactions occurring at the electrodes during the electrolysis.

cathode

ww w.c

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] (b)

Iron is extracted from its oxide by reduction in a blast furnace. (i)

What is the name of the iron ore consisting of iron(III) oxide?

......................................................................................................................................................................... [1] (ii) Explain what is meant by ‘reduction’. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(iii) The main reducing agent in the blast furnace is carbon monoxide, which reacts with iron(III) oxide to produce pure iron. Balance the equation for this reaction. ___CO + Fe2O3

Æ ___CO2 + ___Fe

[2]

om

(iv) A waste product of the blast furnace is called slag. Give one use for slag. ......................................................................................................................................................................... [1] Explain why aluminium is extracted by electrolysis, rather than in a blast furnace.

e.c

..............................................................................................................................................................................

he

ma

ctiv

......................................................................................................................................................................... [2]

ww w.c

(c)

TOTAL / 12

GCSE CHEMISTRY



QUESTIONSHEET 6

A new metal has been discovered. It has the name mancunium with the symbol M. Mancunium reacts violently with water to form a colourless gas and an alkaline solution. The alkaline solution is mancunium hydroxide with formula MOH. Mancunium also forms a chloride salt with formula MCl. (a)

Describe a test to show that the solution formed with water was alkaline.

om

TEST ......................................................................................................................................................................... [1] RESULT

(b)

e.c

......................................................................................................................................................................... [1] Use the information to predict the formula of mancunium oxide.

(c)

ctiv

......................................................................................................................................................................... [1] In which group of the Periodic Table would you place mancunium.

ma

Give a reason for your answer. GROUP

......................................................................................................................................................................... [1]

he

REASON

(d)

ww w.c

......................................................................................................................................................................... [1] Part of the reactivity series for metals is shown below. CALCIUM ZINC IRON COPPER

Rewrite this reactivity series and include the metal mancunium. Give a reason for your position. REACTIVITY SERIES

REASON .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (Continued...)

GCSE CHEMISTRY


(e)

Mancunium was found to react with copper sulphate solution. Give the names of the products of the reaction. ......................................................................................................................................................................... [1]

(f)

Mancunium hydroxide reacts with sulphuric acid to form a salt and water. (i)

Complete the word equation by naming the salt formed in this reaction.

Complete the symbol equation for this reaction. H2SO4 →

________________________________

e.c

+

[2]

he

ma

ctiv

______ MOH

[1]

ww w.c

(ii)

om

mancunium hydroxide + sulphuric acid → _____________________ + water

TOTAL / 11

GCSE CHEMISTRY



QUESTIONSHEET 7

Reactions that give out a large amount of heat have many uses. A company has invented 'cook-in-the-can' meals. A ring is pulled which ignites the chemicals surrounding the can. The chemicals react and produce heat, which cooks the food in the can. One of the reactions used is a mixture of aluminium powder and iron(III) oxide. The aluminium used is finely powdered. (a)(i)

Complete the word equation below for this reaction:

(ii)

Balance the symbol equation for this reaction.

[1]

[1]

e.c

___ Al + Fe2O3 → Al2O3 + ___ Fe (b)

om

aluminium + iron(III) oxide → ______________ + ___________

Use your ideas of the reactivity series of metals to explain why these substances react.

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (c)

Suggest a reason why the aluminium used is powdered.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

(d)(i)

ww w.c

......................................................................................................................................................................... [2] John tried out some reactions in the laboratory that may produce heat. He used a mixture of powdered copper metal and iron(III) oxide. Give a reason why John was unsuccessful.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii)

John found a copy of the reactivity series in a chemistry textbook. It is shown below: magnesium zinc iron silver gold

Use this information to name another metal that John could use that would react with iron(III) oxide. ......................................................................................................................................................................... [1] TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 8

Some students were investigating the reaction between zinc metal and copper sulphate solution. They set up the apparatus as shown in the diagram below.

Thermometer

50 cm3 copper sulphate solution

om

5 g zinc metal

Name a piece of apparatus that could be used to measure out 50 cm3 of copper sulphate solution.

e.c

(a)

......................................................................................................................................................................... [1] Name a piece of apparatus that could be used to measure 5 g of zinc metal.

ctiv

(b)

......................................................................................................................................................................... [1] The reaction is exothermic. Describe what the students would see.

ma

(c)

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [3] (d)

Complete the equation for the reaction Zn + CuSO4 →

(e)

_________ + __________

[1]

Zinc metal was present 'in excess' in this experiment. Explain what is meant by 'in excess'. ......................................................................................................................................................................... [1]

(f)

The students repeated the experiment but added zinc to magnesium sulphate solution. (i)

What would the students see?

......................................................................................................................................................................... [1]

(ii) Explain your answer. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 10

GCSE CHEMISTRY

METALS & THE REACTIVITY SERIES QUESTIONSHEET 9


Reactions were carried out using four different metals - A, B, C and D. The table below shows the results of reacting these metals with air and then with water. metal A B C D (a)

reaction with air changes colour on heating burns in air to form a white solid no reaction changes colour when placed in air

reaction with water no reaction bubbles of gas on surface no reaction fizzes vigorously

From the reactions in the table, give one example of a chemical change.

om

Give a reason for your choice.

[1]

METAL

e.c

.............................................................................................................................................................................. REACTION WITH

..............................................................................................................................................................................

ctiv

REASON

.............................................................................................................................................................................. Use the information in the table to place the four metals in order of reactivity.

[2]

ma

(b)

Which of the four metals is most likely to be an alkali metal? Give a reason for your choice.

ww w.c

(c)

he

MOST REACTIVE ____________________ ____________________ ____________________ LEAST REACTIVE ____________________

The group I metal is likely to be _____________ REASON

......................................................................................................................................................................... [2] (d)

Which of the four metals would be found 'native'? ......................................................................................................................................................................... [1]

(e)

Metal A was found to be copper. Write a word equation for the reaction of copper in air. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(f)

A student wished to try the reaction between metal D and hydrochloric acid. Explain why you should not carry out this reaction. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 10

GCSE CHEMISTRY



The following questions are all about the reactivity of the metals copper, iron, magnesium and potassium. Match up each of the metals with its reaction with water. (The first one has been done for you)

reacts with steam

iron

vigorous reaction in cold water

magnesium

no reaction with steam or water

om

copper

e.c

(a)

reacts reversibly with steam

When metals react with water, they form a metal hydroxide or a metal oxide, depending on their reactivity. From the metals above name a metal which forms: (i)

a metal hydroxide

ma

(b)

[3]

ctiv

potassium

......................................................................................................................................................................... [1]

he

(ii) a metal oxide

......................................................................................................................................................................... [1] When metals react with water they always release a gas. (i)

ww w.c

(c)

Name the gas released when metals react with water.

......................................................................................................................................................................... [1] (ii) Describe a test to prove the identity of the gas Test

......................................................................................................................................................................... [1] .............................................................................................................................................................................. Result .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY



In a series of experiments a small piece of metal was placed in a solution of a metal salt. Here is a list of reactions which take place. 1 2 3 (a)

aluminium + zinc sulphate solution iron + lead nitrate solution zinc + iron(II) sulphate solution

Use the information above to place the metals in order of reactivity, starting with the most reactive.

In another reaction, magnesium was placed in copper(II) sulphate solution. (i)

Write a balanced equation for the reaction between magnesium and copper(II) sulphate.

e.c

(b)

om

[2]

......................................................................................................................................................................... [2]

ctiv

(ii) What would you observe in this reaction?

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (iii) Where in the series you have written would you place copper and magnesium?

he

copper

magnesium

ww w.c

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] (c)

Use your reactivity series to predict whether there will be a reaction between these metals and solutions. Write word equations for any reactions you predict. (i) iron and zinc sulphate

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (ii) aluminium and iron(II) sulphate .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



A student placed a small piece of lithium in a trough. Below is a diagram of what the student observed.

lithium

The experiment was repeated with a piece of sodium. (i)

What other observations would be made?

e.c

(a)

om

trough of water

..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

(ii) Write a balanced symbol equation for the reaction of sodium with water. ......................................................................................................................................................................... [1]

he

(iii) If universal indicator is added to the trough, what colour would it turn? What pH does this represent? ..............................................................................................................................................................................

(b)

ww w.c

......................................................................................................................................................................... [2] The experiment was repeated again, with a small piece of potassium. What new observations would be made? .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

The metals lithium, sodium and potassium are all in Group I of the periodic table. (i) By what other name is Group I known? ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(ii) Why do all metals in Group I react in a similar way? .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (iii) Describe and explain how the reactivity of Group I metals changes on descending the group.

om

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

he

ma

ctiv

e.c

......................................................................................................................................................................... [4]

TOTAL / 13

GCSE CHEMISTRY



QUESTIONSHEET 13

Blackpool pier is made from an iron framework. The iron legs stand in the sea. Salt in sea water tends to speed up rusting. The pier is protected from rusting by connecting blocks of scrap zinc metal to the iron legs of the pier.

om

PIER

ctiv

wire

e.c

sea water

iron leg of the pier

Name the two substances required for iron to rust.

he

(a)

ma

block of scrap zinc

(b)

ww w.c

......................................................................................................................................................................... [1] How does the zinc prevent the iron from rusting? ......................................................................................................................................................................... [1] (c)

Explain why zinc is suitable for this purpose. ......................................................................................................................................................................... [1]

(d)

Why will the zinc only work when the tide is in and the blocks are covered in sea water? .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(e)

Mark on the diagram the direction in which the electrons flow in the wire.

[1]

(Continued...)

GCSE CHEMISTRY


(f)

Predict what would happen if the zinc was replaced with copper metal. Give a reason for your prediction. PREDICTION ......................................................................................................................................................................... [1] REASON

e.c

Salt water appears to make iron rust more quickly than water containing no salt. Describe how you could carry out an experiment in test tubes with some iron nails to investigate this. ..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

ma

..............................................................................................................................................................................

he

......................................................................................................................................................................... [3]

ww w.c

(g)

om

......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 14

The table shows the dates of discovery of some metals. metal potassium sodium magnesium zinc copper

What is the pattern between the reactivity of a metal and its date of discovery?

om

(a)

date of discovery 1807 1807 1755 1746 known since ancient times

..............................................................................................................................................................................

(b)

e.c

......................................................................................................................................................................... [1] A large piece of zinc metal was placed into blue copper sulphate solution. Describe what you would see in this reaction.

ctiv

(i)

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (ii) Complete the word equation for this reaction.

zinc + copper sulphate → ___________________ + ___________________

he

[1]

The temperature of the copper sulphate solution was recorded before the zinc was added and then several minutes later. The results were:

ww w.c

(c)

Temperature at start = 18oC Temperature after reaction = 31oC (i)

Calculate the rise in temperature in this reaction.

......................................................................................................................................................................... [1] (ii) What word is used to describe reactions that give out energy? ......................................................................................................................................................................... [1] (iii) Give two ways in which the reaction could be changed to produce a higher temperature rise. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY Medium Demand Questions


A part of a reactivity series of metals is shown below: SODIUM MAGNESIUM ALUMINIUM CARBON ZINC IRON HYDROGEN COPPER

(a)

om

Use this information to explain as fully as you can the following reactions. A brown solid is formed when a piece of magnesium metal is placed in copper sulphate solution. ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Nothing happens when a piece of copper metal is placed in zinc sulphate solution.

ctiv

(b)

.............................................................................................................................................................................. ..............................................................................................................................................................................

(c)

ma

......................................................................................................................................................................... [2] Iron can be extracted from its oxide using carbon. Aluminium cannot be extracted from its oxide using carbon.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] (d)

Zinc metal reacts with hydrochloric acid to form hydrogen gas. Copper metal does not react with hydrochloric acid. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

(e)

Zinc carbonate decomposes on heating but sodium carbonate does not. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 12

GCSE CHEMISTRY



QUESTIONSHEET 16

A group of students were investigating the effects of 'acid rain'. They decided to look at the effect of acid on metals used as building materials. Lead and copper are used for roofing and iron and aluminium can be used for window frames. Their chemistry book listed these metals in order of their reactivity as follows:

om

ALUMINIUM IRON LEAD COPPER The students tested the metals by adding dilute sulphuric acid to pieces of each of them. Only the iron seemed to give a reaction. What would you see when iron reacted with the acid?

e.c

(a)

......................................................................................................................................................................... [1] Explain why the aluminium did not react with the acid, even when the book said it was more reactive.

ctiv

(b)

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (c)

Suggest why sulphuric acid was used in this test and not any other acid.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

(d)

ww w.c

......................................................................................................................................................................... [2] The reaction with acid did not prove that lead was more reactive than copper. The students had available: 1. small pieces of copper and lead 2. solutions of copper nitrate and lead nitrate. (i)

From these four substances choose two that the students should mix to show that lead is more reactive than copper. 1____________________________

[1]

2____________________________

[1]

(ii) What would you see when the substances were mixed? .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(iii) Write a word equation for the reaction. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (iv) Explain how this reaction proves that lead is more reactive than copper.

om

..............................................................................................................................................................................

ww w.c

he

ma

ctiv

e.c

......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 17

The reactivity series shows the relative reactivities of different metals. Below is a reactivity series for eight metals. sodium calcium magnesium zinc iron lead copper mercury silver

(a)

e.c

Use the series above to answer the following questions.

om


Name the metal which is found uncombined in the Earth’s crust.

(b)

ctiv

......................................................................................................................................................................... [1] Which metal is stored under oil?

......................................................................................................................................................................... [1] Which metal is a liquid at room temperature?

ma

(c)

......................................................................................................................................................................... [1] Which metal is shiny when cut, but tarnishes in a few seconds?

he

(d)

......................................................................................................................................................................... [1] Which metal burns with a bright, white flame?

ww w.c

(e)

......................................................................................................................................................................... [1] (f)

Which metal is extracted from its ore in a blast furnace? ......................................................................................................................................................................... [1]

(g)

Which metal is used to galvanise iron to prevent rusting? ......................................................................................................................................................................... [1]

(h)

Which metal reacts vigorously with cold water? ......................................................................................................................................................................... [1]

(i)

Which metal burns with a brick red flame? ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 18

The 'thermit' reaction is used to weld railway lines together. The reaction mixture contains aluminium metal and iron oxide. The substances are mixed in powder form in a clay pot. The mixture is lit with a magnesium fuse.

om

magnesium fuse

clay pot

ctiv

e.c

reaction mixture

(a)

ma

tap

Complete the word equation for this reaction:

he

aluminium + iron oxide → _________________ + _____________________

[2]

The magnesium ribbon burns at 700oC yet the iron will only melt at 1500oC. Explain why this reaction forms molten iron.

ww w.c

(b)

railway lines

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

Suggest a reason why the aluminium and iron oxide are in powder form. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(d)

Suggest why a tap is needed at the bottom of the clay pot. .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(e)

Suggest a reason for using a clay pot to hold the mixture. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] If copper powder is mixed with iron oxide there is no reaction. Explain why this reaction works with aluminium metal but not copper metal.

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

..............................................................................................................................................................................

he

ma

ctiv

......................................................................................................................................................................... [3]

ww w.c

(f)

TOTAL / 11

GCSE CHEMISTRY



QUESTIONSHEET 19

In an experiment different metals were heated in a Bunsen burner flame for 30 seconds and then removed. The observations are given below.

observation turned black - did not burn burned with white flame no obvious change

om

metal copper magnesium silver

(a)

Place the metals in order of reactivity, starting with the most reactive.

When metals burn in air, an oxidation reaction takes place.

e.c

(b)

[1]

(i) What is meant by ‘oxidation’?

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] Write a word equation for an oxidation reaction which happened in the experiment.

ma

(ii)

......................................................................................................................................................................... [1] In another experiment, a piece of polished copper was placed in a solution of silver nitrate. (i)

What was observed?

he

(c)

(ii)

ww w.c

......................................................................................................................................................................... [1] Explain your answer.

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

In another experiment a piece of polished copper was placed in a solution of magnesium sulphate. (i)

What was observed?

......................................................................................................................................................................... [1] (ii) Explain your answer. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 20

Magnesium reacts very slowly with water. A piece of magnesium is kept under water for a week in the apparatus shown.

magnesium What gas is collected in the test tube?

ctiv

(a)(i)

e.c

water

om

gas

......................................................................................................................................................................... [1] A white solid forms on the surface of the magnesium. What is this solid?

ma

(ii)

......................................................................................................................................................................... [1] (b)

magnesium will react much faster with steam.

he

magnesium

ww w.c

steam

gas

heat

(i)

Name the gas collected in the test tube.

......................................................................................................................................................................... [1] (ii) Suggest two other metals which will react with steam in the same way as magnesium. ......................................................................................................................................................................... [2] (iii) Name a metal that will not react in this way. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


Explain why many items of jewellery are made from gold or silver and not from iron. .............................................................................................................................................................................. ..............................................................................................................................................................................

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [3]

ww w.c

(c)

TOTAL / 9

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 1

The table below gives some information about the halogens: Element

Atomic number

Molecular formula

Bond length/nm

Chlorine Bromine Iodine Astatine

17 35 53 85

C12 Br2 I2 At2

0.20 0.23 0.26 0.29

Bond length = distance between atoms in a molecule nm = nanometres (10-9 metres) Bond energy = energy needed to break the bond in the molecule

(a)

As the atomic number in the halogens increases, what happens to the

e.c

(i)

om

Note:

Bond energy/ kJ per mole 240 195 150

bond length?

ctiv

......................................................................................................................................................................... [1] (ii) bond energy?

......................................................................................................................................................................... [1] What do you think is the bond energy in astatine?

ma

(b)

......................................................................................................................................................................... [1] Describe the relationship between bond length and bond energy as the halogen series is descended.

he

(c)

..............................................................................................................................................................................

ww w.c

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] The solubility of the halogens in water may be summarised as follows: chlorine bromine iodine

dissolves fairly readily dissolves slightly almost insoluble

Chemical reactions occur when the halogens dissolve in water. (d)

What is likely to be the reaction of astatine with water? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(Continued...)

GCSE CHEMISTRY

NON-METALS QUESTIONSHEET 1 CONTINUED

(e)

List the four elements in order of reactivity, placing the most reactive first. .............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

Does your order of reactivity seem to fit with the bond energies?

......................................................................................................................................................................... [1]

e.c

Give a reason for your answer.

..............................................................................................................................................................................

ctiv

..............................................................................................................................................................................

he

ma

......................................................................................................................................................................... [2]

ww w.c

(f)

om

......................................................................................................................................................................... [2]

TOTAL / 12

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 2

When sulphur is heated in air, a colourless, poisonous gas with an unpleasant, choking smell is formed. If this gas is collected, dried, then cooled to below –10oC, it forms a colourless liquid. Dry pH paper dipped into this liquid does not change colour, but damp pH paper dipped into the liquid shows a pH of less than 7. (a)

What is the name of the colourless gas? ......................................................................................................................................................................... [1] What is the boiling point of the colourless liquid?

om

(b)

......................................................................................................................................................................... [1] (c)

Why does the colourless liquid not affect the dry pH paper?

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] When damp pH paper is used, the colourless liquid becomes acidic. How do you know this?

ctiv

(d)

......................................................................................................................................................................... [1]

Write a balanced chemical equation for the reaction between the colourless gas named in part (a) with oxygen.

he

(e)

ma

If the colourless gas from above is reacted with oxygen at 450oC and in the presence of vanadium pentoxide, sulphur trioxide forms as a colourless gas, which then cools to colourless crystals. If water is added to the crystals, a fiercely exothermic reaction takes place and sulphuric acid forms.

......................................................................................................................................................................... [2] The vanadium pentoxide is recovered after the above reaction. What is its purpose in the reaction?

ww w.c

(f)

......................................................................................................................................................................... [1] (g)

What is meant by an ‘exothermic reaction’? ......................................................................................................................................................................... [1]

(h)

Write a balanced chemical equation for the reaction of sulphur trioxide with water. ......................................................................................................................................................................... [2]

(i)

In fact, this reaction is much too exothermic to carry out safely. It would spray sulphuric acid all around the room. In practice, the sulphur trioxide is added to 98% sulphuric acid, where it reacts with the 2% water present to form more sulphuric acid. Why is the reaction much safer when carried out like this? .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 13

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 3

The diagram below shows an apparatus that can be used to react chlorine with iron. iron wire excess chlorine

dry chlorine product

HEAT

Describe the appearance of the Group VII element chlorine.

om

(a) (i)

......................................................................................................................................................................... [1]

e.c

(ii) What compound is formed during the reaction that takes place?

......................................................................................................................................................................... [1]

..... Fe (s) +

ctiv

(iii) Complete and balance the following symbol equation for the chemical change that takes place. ............ (g) ς

..... FeCl (s)

[2]

3

ma

(iv) Give one reason why this reaction must be carried out in a fume cupboard. ..............................................................................................................................................................................

The element iodine is below chlorine in Group VII of the Periodic Table. If iodine was allowed to react with iron wire, state whether you would expect this reaction to be more vigorous, less vigorous or about the same as the reaction between chlorine and iron wire.

ww w.c

(b)

he

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] (c)

Group I elements also react with Group VII elements. (i) Complete and balance the symbol equation for the reaction between sodium and bromine.

..... Na (....)

+

Br (....) 2

ς

.....NaBr (s)

[2]

(ii) If the following pairs of elements were allowed to react together, choose the pair that would be most reactive and give an explanation for your choice. lithium and fluorine sodium and chlorine potassium and chlorine potassium and fluorine (Continued...)

GCSE CHEMISTRY


The most reactive pair is: .............................................................

[1]

Give an explanation for your choice. ..............................................................................................................................................................................

ww w.c

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [2]

TOTAL / 11

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 4

For each of the following pairs of substances describe how you would distinguish between them by giving one chemical test in each case. Describe your observation on both substances. (i)

Nitrogen and oxygen.

..............................................................................................................................................................................

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Hydrogen and chlorine.

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

(iii) Carbon dioxide and sulphur dioxide.

ctiv

......................................................................................................................................................................... [2]

ma

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

he

......................................................................................................................................................................... [3]

ww w.c

(iv) Water and ammonia solution.

.............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 10

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 5

Sulphuric acid is manufactured industrially by the contact process. During the early part of the process, sulphur is reacted with oxygen to give an oxide A. This substance is then converted into sulphur trioxide by reacting A with the element B. (a) (i)

Calculate the simplest formula of the oxide of sulphur A from the following information. 3.2 g of sulphur gave 6.4 g of the oxide A. Please show how you worked out your answer. Ar(S) = 32; Ar(O) = 16.

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [3]

(b)

......................................[1]

ctiv

(ii) Name the element B.

The reaction between A and B to give the gas sulphur trioxide is reversible. Explain the term ‘reversible’ and complete and balance the chemical equation.

ma

(i) A reversible reaction is

..............................................................................................................................................................................

he

......................................................................................................................................................................... [1] (ii) Complete and balance the equation;

(c)

ww w.c

.............. + ............

....... SO3

[2]

Both oxygen and sulphur are in the same group of the Periodic Table. One method for both to react is to become an ion X2-. Explain in terms of their electronic structures why oxygen is more reactive towards this change than sulphur. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 6

Plants need many substances for healthy growth and for the chemical reactions which occur within them. Most of these substances are absorbed in solution in water through the roots. The three main essential elements which plants need are nitrogen, phosphorus and potassium. These elements may be supplied naturally by the soil, but often we need to add one or more of them in the form of fertilisers. A fertiliser is sold in a bag labelled with its name followed by three numbers which indicate, respectively, the percentages of nitrogen, phosphorus and potassium present. e.g. Regular 20 – 10 – 12 means that the fertiliser is called regular and contains 20% nitrogen, 10% phosphorus and 12% potassium. Such fertilisers are known as NPK fertilisers. Here is a list of some common fertilisers.

e.c

Why are these fertilisers known as NPK fertilisers?

ctiv

(a)

om

Universal 15 – 15 – 15 Extra grass 29 – 5 – 5 Double season PK for fertile soils 0 – 20 – 20 Maincrop potato 10 – 10 – 15 + 4.5 Mg Concentrated maincrop potato 15 – 15 – 19 Granphos 2 – 40 – 0 Barley for high potash clay soils 29 – 13 – 0 Winter wheat 9 – 23 – 18

..............................................................................................................................................................................

(b)

ma

......................................................................................................................................................................... [2] Name the essential element which: (i)

is already present in fertile soil and so does not need adding.

he

......................................................................................................................................................................... [1]

ww w.c

(ii) favours green growth (e.g. grass).

......................................................................................................................................................................... [1] (iii) potatoes need in extra high concentration. ......................................................................................................................................................................... [1] (c)

Name an element, other than nitrogen, phosphorus or potassium, which potatoes need. ......................................................................................................................................................................... [1]

(d)

What percentage of nitrogen would be supplied by a fertiliser of pure ammonium nitrate NH4 NO3? (Relative atomic masses: H = 1, N = 14, O = 16). .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

(Continued...)

GCSE CHEMISTRY


A farmer was offered a choice of potassium nitrate or urea as a fertiliser. Although much more expensive per gram of nitrogen, he chose potassium nitrate. Give one reason which may have influenced his choice. ..............................................................................................................................................................................

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [1]

ww w.c

(e)

TOTAL / 10

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 7

Phosphorus (P) is directly below nitrogen in the periodic table. (a)

Write down the electronic configuration of phosphorus. ......................................................................................................................................................................... [1] Write down the formula of the compound you would expect phosphorus to form with hydrogen, and use a dot and cross diagram to show how it is formed.

e.c

om

(b)

Formula .................................................................................................................................................. [3] Would you expect this compound to be a solid, a liquid or a gas at room temperature?

ctiv

(c) (i)

......................................................................................................................................................................... [1] (ii) Explain your reasons.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

he

Give one use for phosphorus-containing compounds

......................................................................................................................................................................... [1]

ww w.c

(d)

TOTAL / 8

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 8

(b)

Solid sulphur consists of rings of eight atoms. Fill in the gaps in the table below to show the changes in appearance and structure of sulphur when it is heated. appearance Yellow solid Melts to form a _____ _____ liquid

structure Rings of 8 atoms

Boils

Separated sulphur atoms and groups of atoms

om

(a)

[4]

Sulphur exists in two crystalline forms. What are different crystalline forms of the same element known as?

When molten sulphur is cooled slowly, needle-like crystals form under the surface. Why do some rocks contain crystals when they are split open?

ctiv

(c)

e.c

......................................................................................................................................................................... [1]

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

These crystals change slowly to another form with rhombic-shaped crystals as they cool. (i) What changes are seen as the needle-like crystals cool?

he

......................................................................................................................................................................... [1] (ii) What changes would be seen in the rhombic crystals as they cool? ......................................................................................................................................................................... [1]

ww w.c

(d)

TOTAL / 9

GCSE CHEMISTRY

NON-METALS QUESTIONSHEET 9


Tooth decay in the UK is a serious problem. About 7000 sets of dentures are supplied each year to school children alone. This is a waste of healthy teeth and money. It has been suggested that the presence of fluoride ions, F , in drinking water helps to prevent tooth decay. The data in the following table come from six different areas of the country, where fluoride ions occur naturally in the water supply.

On the chart below plot a graph of DMF against ppm of fluoride concentration. 800

ma

600

he

400

200

0

ww w.c

DMF teeth per 100 children

[2]

ctiv

(a)

DMF = decayed, missing or filled ppm = parts per millionS

e.c

Note:

fluoride concentration/ppm 0.5 0.9 2.6 0.1 1.9 1.2

om

DMF teeth per 100 children 430 350 240 720 250 300

0.5

1.0

1.5

2.0

2.5

3.0

Fluoride concentration/ppm

(b)

Does your graph support or contradict the suggestion that fluoride ions in drinking water help to prevent tooth decay? ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


It has been found in a much wider study from many more areas in the UK that similar results are obtained. Also, the presence of small amounts of fluoride in the water does not appear to be at all harmful. As a result, it has been suggested that in areas where there is no natural fluoride in the water, drinking water should undergo fluoridation i.e. should have fluoride added. (c)

Give a reason why fluoridation might be a good idea in areas with no natural fluoride in the drinking water. ......................................................................................................................................................................... [1] Give one argument which might be used against fluoridation of water supplies.

om

(d)

..............................................................................................................................................................................

Suggest two other ways, other than fluoridation of water, in which people could take small amounts of fluoride ions

ctiv

..............................................................................................................................................................................

he

ma

......................................................................................................................................................................... [2]

ww w.c

(e)

e.c

......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY



The table below gives some information about six different gases. Formula of molecule CH4 NH3 N2 O2 CO2 SO2

Mass of one mole of molecules/g 16 17 28 32 44 64

Volume occupied by 1g at rtp/dm3 1.50 1.40 0.86 0.76 0.54 0.38

(a)

om

rtp = room temperature and pressure relative atomic masses: H=1, C=12, N=14, O=16, F=19, Ar=40 Give the name of the molecules listed in the first column.

e.c

CH4 = ................................................................................................................................................... [1] NH3 = ................................................................................................................................................... [1]

ctiv

N2 = ................................................................................................................................................... [1] O2 = ................................................................................................................................................... [1] CO2 = ................................................................................................................................................... [1]

[2]

he

On the chart below plot a graph of volume against mass of one mole.

ww w.c

1.5

1.3 Volume at rtp/dm3

(b)

ma

SO2 = ................................................................................................................................................... [1]

1.1

0.9

0.7

0.5

0.3 10

20

30

40

50

60

70

mass of one mole/g

(Continued...)

GCSE CHEMISTRY


(c)

Use your graph to find the volume at rtp occupied by: (i)

1g of ethene, C2H4 .................................................................................................................................. [1]

(ii) 1g of argon .............................................................................................................................................. [1] (d) (i)

What is the mass of one mole of molecules of a gas for which 1g at rtp occupies 0.52 dm3?

om

......................................................................................................................................................................... [1] (ii) If the molecule is made up of nitrogen and oxygen only, what is its formula? Show your working.

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

Determine the volume at rtp occupied by 1g of hydrogen fluoride, HF. Show your working.

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

......................................................................................................................................................................... [5]

ww w.c

(e)

ctiv

......................................................................................................................................................................... [3]

TOTAL / 19

GCSE CHEMISTRY



The following table contains some information about Group VII of the Periodic Table. Element Formula Atomic number Melting point (oC) fluorine F2 9 -223 chlorine C12 17 -103 bromine Br2 35 -7 iodine I2 53 114 (a)(i)

Colour pale yellow yellow-green red-brown purple-black

Name the element with the lowest melting point.

om

......................................................................................................................................................................... [1] (ii) Chlorine is a diatomic gas. Explain the meaning of ‘diatomic’.

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [1]

ctiv

(iii) Give the electronic structure of chlorine.

......................................................................................................................................................................... [1] (iv) Explain how chloride ions are formed from chlorine atoms.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Astatine, At, is another member of Group VII with an atomic number of 85. (i)

he

(b)

Give the formula for astatine.

ww w.c

......................................................................................................................................................................... [1] (ii) Describe the appearance of astatine.

......................................................................................................................................................................... [1] (iii) Give the number of electrons in the outer shell of astatine. ......................................................................................................................................................................... [1] (iv) Astatine is expected to form a compound with hydrogen in a similar way to chlorine and hydrogen. By means of a labelled diagram, show how the atoms are bonded together. Name this type of bonding. Diagram

[2] Type of bonding. .................................................................................................................................. [1] TOTAL / 11

GCSE CHEMISTRY



The table below shows some properties of elements A, B, C, D and E. (The letters are not chemical symbols.)

A B C D E

Melting point (oC) 119 -7 98 1083 -259

Boiling point (oC) 444 59 883 2336 -253

Conducts heat no no yes yes no

Brittle

Reaction with water

Shiny

yes no no no no

insoluble slightly soluble reacts insoluble slightly soluble

no no yes yes no

om

Element

Give the letter of the element which is a liquid under room conditions.

(b)

Give the letters of all the elements that are non-metals giving two reasons for your answer. (i)

e.c

(a)

The elements that are non-metals are

..........................................[3]

ctiv

(ii) Reasons.

...................................[1]

..............................................................................................................................................................................

Elements A and E when heated can react together to give a gas. Name the type of bonding you would expect this compound to have. Give a reason for your answer. Type of bonding Reason.

he

(c)

ma

......................................................................................................................................................................... [1]

......................................................[1]

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

Gas E has no colour or smell. It burns in oxygen giving a vapour which condenses on a cold surface as a colourless neutral liquid. The gas E has a number of important uses including the industrial manufacture of ammonia. Name the gas E. Gas E is

.....................................[1]

TOTAL / 9

GCSE CHEMISTRY



Diamond and graphite are two allotropes of the element carbon. (a)

Explain the meaning of allotropy .............................................................................................................................................................................. ......................................................................................................................................................................... [1] Draw the structure of both diamond and graphite.

om

(b)

(ii) Graphite.

(c)

[4]

ma

ctiv

e.c

(i) Diamond

Use the above structures to explain the following. (i)

Diamond is a very hard substance often used to cut and engrave glass.

he

..............................................................................................................................................................................

ww w.c

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Graphite conducts electricity and is used as electrodes in industry and as positive terminals in batteries. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY



The following box contains non-metals and their atomic numbers.

helium 2,

carbon 6,

nitrogen 7,

oxygen 8,

fluorine 9,

sulphur 16,

chlorine 17,

bromine 35.

om

hydrogen 1,

Use only elements from these given non-metals to answer the following questions. Each element may be used once, more than once or not at all.

(i)

a liquid at room temperature,

(ii) has four electrons in its outer shell, (iii) has the electronic structure 2, 8, 7

ma

(iv) forms an ion with the formula X2-. (b)

e.c

Name one element which is

ctiv

(a)

.....................................[1] ....................................[1] ....................................[1] ....................................[1]

Nitrogen reacts with hydrogen to give the gas ammonia.

Formula.

(c)

ww w.c

Type of bonding.

he

Give the formula and the type of bonding in ammonia.

....................................[1]

Name the element which readily burns in air with a pale blue flame giving off an unpleasant smelling gas which is one of the main causes of acid rain. The element is

(d)

....................................[1]

....................................[1]

Two elements X and Y form compounds with hydrogen with the formulae H2X and YH4. Name the elements X and Y. Element X is

....................................[1]

Element Y is

....................................[1]

TOTAL / 9

GCSE CHEMISTRY



(a) Give two physical properties of hydrogen. (i) ............................................................................................................................................................. [1] (ii) . ........................................................................................................................................................... [1] (b) Some pure hydrogen was carefully burnt on a cold surface as shown in the diagram.

om

hydrogen burning Pure dry hydrogen

drops of liquid A

e.c

glass tube

Name two chemicals that could be used to make hydrogen in the laboratory.

ctiv

(i)

cold surface

................................................. and ....................................................

[2]

(ii) Give the precaution that must be taken before hydrogen is ignited.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] Name the liquid A.

......................................[1]

(iv)

Give a simple chemical test and observation to confirm the identity of the liquid.

he

(iii)

ww w.c

Test. ................................................................................................................................................................. [1] Observation. ......................................................................................................................................................... ......................................................................................................................................................................... [1] (c) One of the first uses of hydrogen was in airships since it is the lightest of all gases. Unfortunately it reacts violently with the oxygen in the air which has led to a number of disasters. Name the safer gas which is used in present day airships. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



The table below contains some information about four different substances A, B, C and D. (The letters are not chemical symbols.) Study the table carefully and answer the given questions.

A B C D

above 500 below 500 above 500 above 500

Conducts electricity when solid yes no no no

om

Boiling point (oC)

State which substance is most likely to be:(i)

diamond,

e.c

(a)

Substance

(ii) iodine,

(b)

...............................[1] ...............................[1] ...............................[1]

ctiv

(iii) copper .

Conducts electricity when melted yes no no yes

The four substances are diamond, copper, iodine and sodium chloride. Which of these substances best fits the following descriptions? Atoms bonded by sharing electrons to form small molecules.

ma

(i)

......................................................................................................................................................................... [1]

he

(ii) Atoms bonded by sharing electrons to form giant covalent structures. ......................................................................................................................................................................... [1]

ww w.c

(iii) Atoms bonded by electron transfer to form giant ionic structures. ......................................................................................................................................................................... [1] During the electrolysis of molten sodium chloride the chloride ion, Cl-, is attracted towards the positive electrode and releases chlorine gas, Cl2.

(c)

(i)

Explain the meaning of the term electrolysis.

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (ii) Complete the equation that takes place at the positive electrode. __ Cl- → C12 ________

[2]

TOTAL / 9

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 17

The following table gives some information about gases which are found in the air.

(a)

Soluble in water? no slightly no fairly no no no no

om

Boiling point/oC -196 -183 -186 -40 (sublimes) -246 -269 -153 -108

Gas nitrogen oxygen argon carbon dioxide neon helium krypton xenon

As well as the above, which other gas is normally found in the air?

(b)

e.c

......................................................................................................................................................................... [1] Which of the above gases becomes liquid at the lowest temperature?

(c)

ctiv

......................................................................................................................................................................... [1] Carbon dioxide sublimes at –40oC. What would you observe if carbon dioxide gas was cooled to this temperature?

(d)

ma

......................................................................................................................................................................... [1] If a mixture of liquid nitrogen and liquid oxygen was allowed to warm up, which one would boil first?

(e)

he

......................................................................................................................................................................... [1] What is the name of the process which allows nitrogen and oxygen to be separated from liquid air by warming?

(f)

ww w.c

......................................................................................................................................................................... [1] State the approximate percentages by volume of nitrogen and oxygen in the air.

[2]

Nitrogen ................................% Oxygen .................................% (g)

The percentages of nitrogen and oxygen in the air which has been boiled out of water are different to those given in part (f). Why is this? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(Continued...)

GCSE CHEMISTRY


(h)

Nitrogen and oxygen are both obtained by allowing liquid air to warm up. Why is oxygen more expensive than nitrogen? ......................................................................................................................................................................... [1] Green plants need carbon dioxide for photosynthesis. How can some green plants continue to live under water?

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [1]

ww w.c

(i)

TOTAL / 11

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 18

The flow chart shows some of the reactions and changes involved in carbon compounds. carbon monoxide CO

carbon dioxide

D

CO2 solution B goes milky/ cloudy

C

calcium carbonate

plants

om

E solid A

...............................................

B is

...............................................

(b) Name the different processes C, D and E. ...............................................

D is

...............................................

E is

...............................................

[1]

[1] [1]

ma

C is

[1]

ctiv

A is

e.c

(a) Name the chemical substances labelled A and B .

[1]

he

(c) How can carbon dioxide be converted into carbon monoxide? ......................................................................................................................................................................... [2]

ww w.c

(d) Give one important use of carbon dioxide.

......................................................................................................................................................................... [1] (e) Carbon is often used as a reducing agent. When a mixture of carbon and copper oxide are heated the copper oxide is reduced to copper. Complete and balance the equation for the reaction.

C + ..... CuO (f)

→

... Cu + ..........

[2]

Carbon and silicon both belong to Group 4 of the Periodic Table of elements. They form oxides with similar formulae CO2 and SiO2. In terms of structures explain why carbon dioxide is a gas at room conditions but silicon dioxide has a very high melting point.

.............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 12

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 19

Use The Periodic Table to answer this question. (a)

Give the symbol for the element (i)

oxygen

......................................................................................................................................................................... [1] potassium

om

(ii)

.............................................................................................................................................................................. Give the name of the element with the symbol (i)

C

[1]

e.c

(b)

..............................................................................................................................................................................

ctiv

(ii) Na

.............................................................................................................................................................................. Complete the following table.

Chemical formula ZnO FeS NaOH KC1

he

Substance zinc oxide iron sulphide sodium hydroxide

ma

(c)

Elements present zinc and oxygen

potassium and chlorine

The chemical formula for carbon monoxide is CO. (i)

ww w.c

(d)

[3]

How many different elements are represented in carbon monoxide?

......................................................................................................................................................................... [1] (ii) Give the total number of atoms the formula CO represents. ......................................................................................................................................................................... [1] (e)

The chemical formula for sulphuric acid is H2SO4. (i)

How many different elements are present in sulphuric acid?

......................................................................................................................................................................... [1] (ii) Give the total number of atoms present in H2SO4. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY

NON-METALS


QUESTIONSHEET 20

The table below gives some information about halogens. Element Fluorine Chlorine Bromine Iodine Astatine

Melting point/oC -220 -101 -7 +114

Atomic number 9 17 35 53 85

Boiling point/oC -188 -35 +58 +183

As the atomic number increases what happens to the (i)

om

(a)

Atomic symbol F C1 Br I At

melting point?

......................................................................................................................................................................... [1]

e.c

(ii) boiling point?

......................................................................................................................................................................... [1]

(i)

ctiv

Are these elements solids, liquids or gases at room temperature (20oC)?

(b)

fluorine is a ............................................................................................................................................. [1]

(ii) chlorine is a ............................................................................................................................................ [1]

ma

(iii) bromine is a ............................................................................................................................................ [1] (iv) iodine is a ................................................................................................................................................ [1] In which physical state do you think astatine exists at room temperature?

he

(c)

......................................................................................................................................................................... [1]

fluorine chlorine bromine iodine (d)

ww w.c

The behaviour of the halogens with water may be summarised as follows: violent reaction dissolves fairly readily dissolves slightly almost insoluble

What is likely to be the behaviour of astatine with water? ......................................................................................................................................................................... [1]

(e)

List the five elements in order of reactivity, placing the most reactive first. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 10

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 1

(a)

Crude oil is the raw material of the petrochemical industry. Describe how crude oil was formed. .............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [3]

e.c

(b) The first stage in the processing of crude oil is fractional distillation. The process is illustrated in the diagram below.

ctiv

Petroleum gases, b.p. –160-40oC

ma

Gasoline, b.p. 40-75oC

he

Naphtha, b.p. 75-150oC

Vapour of crude oil

ww w.c

Kerosene (paraffin), b.p. 150-240oC

Bottled gas and chemicals

Petrol

Chemicals

Jet fuel

Diesel oil, b.p. 220-250oC

Diesel fuel

Lubricating oil, b.p. 250-350oC

Lubricants and chemicals

Fuel oil 350oC

Fuel for ships

Bitumen

Roads and roofing felt

(Continued...)

GCSE CHEMISTRY

PRODUCTS FROM OIL

QUESTIONSHEET 1 CONTINUED (i)

Explain how fractional distillation can be used to separate crude oil.

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

om

......................................................................................................................................................................... [3] (ii) From which fraction is petrol obtained?

......................................................................................................................................................................... [1]

e.c

(iii) Which fraction provides the chemical feedstock for the petrochemical industry? ......................................................................................................................................................................... [1]

ctiv

All of the chemicals in crude oil are hydrocarbons. What are hydrocarbons?

he

ma

......................................................................................................................................................................... [2]

ww w.c

(c)

TOTAL / 10

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 2

Crude oil is a mixture of many different hydrocarbons. The process by which it can be separated can be demonstrated in the laboratory using the apparatus shown below. thermometer clamp delivery tube

om

crude oil soaked into mineral wool

(a) (i)

What is the name for this process of separation?

e.c

cold water

heat

(ii) What is the purpose of the mineral wool?

ctiv

......................................................................................................................................................................... [1]

In a typical experiment, four different fractions can be collected. The properties of these fractions are summarised below. b.p. range (oC)

A

up to 80

B

80 to 160

C D

viscosity

he

fraction

160 to 250

colour

very low

colourless

low

pale yellow

ww w.c

(b)

ma

......................................................................................................................................................................... [1]

high

yellow

250 to 320

Complete the table. (c) (i)

how it burns easily clean flame quite easily smoky flame difficult to light very smoky flame

[3]

Suggest, with reasons, which fraction would be used to provide: fuel for a motor car engine.

Fraction ................................................................................................................................................ [1] Reason.................................................................................................................................................. [2] (ii)

a lubricating oil. Fraction ................................................................................................................................................. [1] Reason................................................................................................................................................... [1] TOTAL / 10

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 3

Many of the hydrocarbons obtained from crude oil belong to the alkane homologous series. (a)

What is a hydrocarbon? ......................................................................................................................................................................... [2]

(b)

State two general characteristics of any homologous series.

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

The first and fourth members of the alkane series are methane, CH4, and butane, C4H10. What is the formula of hexane, the sixth member of the series?

e.c

(c)

......................................................................................................................................................................... [1] The atoms of the hydrocarbon, C4H10, can be arranged in two different ways. Draw the structural formulae for the two arrangements of this hydrocarbon.

ww w.c

he

ma

(i)

ctiv

(d)

[2]

(ii) Which of the two structural formulae you have drawn will have the higher boiling point? ......................................................................................................................................................................... [1] (iii) Explain your answer to part (ii).

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 10

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 4

Crude oil is a mixture of many compounds. In order to convert it into useful products it must pass through a number of processes. (a)

One of the products of the first processing stage is naphtha. What is the name of the process by which naphtha is produced? ......................................................................................................................................................................... [1] Naphtha is then subjected to another process that can produce ethene as one of the products. What name is given to this process?

om

(b)

......................................................................................................................................................................... [1] Ethene can be used for a number of other processes, one of which makes poly(ethene). What is the name of this process?

e.c

(c)

......................................................................................................................................................................... [1]

(e)

n C

C

H

H

ma

H

he

H

ctiv

Complete the following structural equation for the formation of poly(ethene).

ww w.c

(d)

[2]

Describe two environmental problems which are associated with the disposal of waste plastics. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 5

This question is about the alkene, ethene, C2H4, which is an unsaturated hydrocarbon. (a)

What is meant by ‘unsaturated’? ......................................................................................................................................................................... [1]

(b)

What is the general formula of alkenes? ......................................................................................................................................................................... [1] Ethanol can be produced from ethene by direct hydration. C2H4

+

H2O

Æ

C2H5OH

e.c

Under what conditions is this reaction carried out?

om

(c)

..............................................................................................................................................................................

ma

(e)

Draw the structural formula of ethanol

[1]

Ethane is a saturated hydrocarbon. Describe a simple test that would enable you to distinguish between ethene and ethane.

he

(d)

ctiv

......................................................................................................................................................................... [2]

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (f)

Chlorethene (vinyl chloride) can be made from ethene.

Cl

H

C

C

H

H

Chloroethene can be used to produce poly(chloroethene) or PVC. Draw a section of a PVC molecule containing four carbon atoms.

[2] TOTAL / 9

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 6

Cracking is an important process in the petrochemical industry. (a) (i)

What are the conditions for carrying out cracking?

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

ctiv

e.c

om

(ii) Cracking can be demonstrated in the laboratory. Draw a labelled diagram of an apparatus that would enable you to crack a sample of liquid paraffin and to collect the gaseous product.

he

[4]

(iii) Give one piece of evidence that the product contains smaller molecules than the starting material.

(b)

ww w.c

......................................................................................................................................................................... [1] The starting material is said to contain only saturated hydrocarbons, whereas the product will contain unsaturated ones. What is the difference between a saturated and an unsaturated hydrocarbon? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 7

Ethane is an alkane hydrocarbon. (a) (i)

Draw the structural formula of ethane.

(ii) Ethane is said to be saturated. What does this term mean?

om

[1]

......................................................................................................................................................................... [1]

e.c

(iii) Why is it not possible to make polymers from ethane?

(i)

Poly(butene) can be made from butene. Draw one possible structure of butene.

ma

(b)

ctiv

......................................................................................................................................................................... [1]

Draw a section of a poly(butene) having eight carbon atoms.

(c)

poly(butene) is a thermosoftening plastic. Other plastics may be described as thermosetting.

ww w.c

(i)

he

(ii)

[1]

[1]

Suggest one use for a thermosetting plastic.

......................................................................................................................................................................... [1] (ii) Describe how a sample of a plastic could be tested to find out whether it is thermosetting or thermosoftening. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] TOTAL / 9

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 8

The diagram below shows some of the reactions of ethene, C2H4. ethane, C2H6

Liquid A bromine

gas B, catalyst C

ethene, C2H4 steam, catalyst D

high pressure, heat, initiator

om

liquid F

solid E

Give the names of each of the lettered substances.

(i)

e.c

(a)

liquid A

ctiv

.............................................................................................................................................................................. (ii) gas B

(iii) catalyst C

ma

..............................................................................................................................................................................

(iv) catalyst D

he

..............................................................................................................................................................................

(v) solid E

ww w.c

..............................................................................................................................................................................

.............................................................................................................................................................................. (vi) liquid F

......................................................................................................................................................................... [6] (b)

Write a chemical equation for the reaction between ethene and steam to form liquid F. ......................................................................................................................................................................... [2]

(c)

Ethene can be converted into ethane by reaction with gas B in the presence of catalyst C. State one commercial application of this type of reaction. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY

PRODUCTS FROM OIL QUESTIONSHEET 9


(a) (i)

formula CH4 C2H6 C3H8 C4H10 C5H12 C6H14 C7H16 (ii) C9H20 C10H22

boiling point (oC) -161 -88 -42 0 36 69 126 151 174

e.c

name methane ethane propane butane (i) hexane heptane octane nonane decane

om

The following table gives some data about the first ten members of the alkane homologous series.

Give the name of the alkane (i), C5H12.

(ii)

ctiv

......................................................................................................................................................................... [1] Give the formula of the alkane (ii), octane.

ww w.c

he

ma

......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY

PRODUCTS FROM OIL QUESTIONSHEET 9 CONTINUED [4]

he

ma

ctiv

e.c

om

Plot a graph of boiling point (vertical axis) against number of carbon atoms (horizontal axis)

ww w.c

(b) (i)

(Continued...)

GCSE CHEMISTRY

PRODUCTS FROM OIL QUESTIONSHEET 9 CONTINUED

(ii) Use the graph to estimate the boiling point of heptane. ......................................................................................................................................................................... [1] There are three hydrocarbons with the molecular formula, C5H12.

ma

ctiv

e.c

om

Draw the structural formulae of all three hydrocarbons.

he

(i)

[3]

ww w.c

(c)

TOTAL / 10

GCSE CHEMISTRY


QUESTIONSHEET 10

Ethene can be made into poly(ethene). Draw a section of a poly(ethene) molecule containing at least six carbon atoms.

om

(a)

PRODUCTS FROM OIL

ctiv

e.c

(b) Poly(ethene) is a thermsoftening plastic. Draw the structure of a thermosoftening plastic.

[2]

ma

(c)

[2]

Explain why poly(ethene) is a good material for use in carrier bags.

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] About thirty years ago, most carrier bags were made from paper, whereas most today are made from poly(ethene). Explain why this change has taken place.

ww w.c

(d)

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY



The table below gives some information about monomers and the polymers that are made from them. name and structure of monomer

H

C H

poly(ethene)

H

H

C

C

C

H

H

H

H

Cl

C

C

H

H

H

Cl

C

C

H

H

poly(chloroethene)

om

chloroethene

H

e.c

ethene

name and structure of polymer

phenylethene

C6H5

C

C

H

H

n

(i)

ctiv

(ii)

H

n

n

Complete the table.

(b)

What structural feature do these monomers have which enables them to be polymerised?

ma

(a)

[2]

he

......................................................................................................................................................................... [1] Poly(chloroethene) is used to make coverings for electrical cables. It has replaced the use of rubber. (i)

ww w.c

(c)

State two properties of poly(chloroethene) that are common to plastics in general, and make it suitable for this use.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii)

State two ways in which poly(chloroethene) is better than rubber for this use.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

Describe two environmental problems that are associated with the disposal of plastics.

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 9

GCSE CHEMISTRY

PRODUCTS FROM OIL

QUESTIONSHEET 12


The table below gives some information about monomers and the polymers that can be made from them. monomer

structure

ethene

H

H

C

polymer

H

H

C

C

C

H

H

H

H

H

CH3

C

C

H

H

e.c

A

poly(tetrafluoroethene)

ma

ctiv

D

Complete the table.

(b)

What is meant by the term ‘monomer’?

B

F

F

C

C

F

F

n

[4]

he

(a)

n

om

poly(ethene)

propene

C

structure

(c)

ww w.c

......................................................................................................................................................................... [1] What is meant by the term ‘polymer’?

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

Write down the molecular formula of tetrafluoroethene. ......................................................................................................................................................................... [1]

(e)

Poly(ethene) can sometimes be used in place of steel. Give one advantage of using poly(ethene) in this way. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY

PRODUCTS FROM OIL

QUESTIONSHEET 13


To which homologous series does decane belong? ......................................................................................................................................................................... [1]

(b)

Cracking decane can produce the following products: ethene C2H4

pentane C5H12

propene C3H6

om

Which of these are unsaturated? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(i)

e.c

Cracking decane can sometimes produce just two types of molecule. If one of these products is ethene, give the formula and name of the other one. formula

ctiv

(c)

......................................................................................................................................................................... [1] (ii) name

(d)

ma

......................................................................................................................................................................... [1] What are the economic advantages of cracking?

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (e)

Name two chemicals that can be made from ethene. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY


PRODUCTS FROM OIL

QUESTIONSHEET 14

Some of the products of the distillation of crude oil are used as fuels. To find out the products formed when hydrocarbons burn, the apparatus below is used.

Thistle funnel

Ice

om

To vacuum pump (this draws the gaseous combustion products through the apparatus)

(a)

TUBE A A colourless liquid condenses here

Name the product collected in tube A.

ctiv

Kerosene (paraffin) in spirit burner

e.c

Limewater

(b)

ma

......................................................................................................................................................................... [1] What will happen to the limewater?

Some fuels leave a black deposit on the inside of the thistle funnel. (i) What is this deposit?

ww w.c

(c)

he

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] (ii) Why does it form?

......................................................................................................................................................................... [1] (iii) What other product could be formed under these circumstances? ......................................................................................................................................................................... [1]

TOTAL / 5

GCSE CHEMISTRY



Ethene can be used to make ethanol, C2H5OH. (a)

Write an equation for this reaction. ......................................................................................................................................................................... [2] Ethanol can be used to make substances known as esters. Esters are often used as flavourings. The table shows some esters. FLAVOURING

FORMULA OF ESTER CH3

C

BANANA O C

O

C5H11

O

C5H11

O

C2H5

e.c

C3H7 APRICOT

om

(b)

O

C3H7

C

ctiv

PINEAPPLE

O

Which element is present in esters, which is not present in hydrocarbons?

ma

(i)

......................................................................................................................................................................... [1]

he

(ii) An ester found in apple flavouring contains five carbon atoms, ten hydrogen atoms and two oxygen atoms. Complete the formula of the apple flavouring given below. C

ww w.c

C3H7

O

O

[1]

(iii) Many of the esters are used as flavourings in food additives. Give two arguments for and two against the use of food additives. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [4]

(Continued...)

GCSE CHEMISTRY

PRODUCTS FROM OIL QUESTIONSHEET 15 CONTINUED

(c)

Ethanol can be made from the fermentation of sugars. In Brazil, ethanol produced in this way is added to petrol. The mixture is known as Gasohol. (i) Suggest why this is an economic process in Brazil, but would not be possible in Britain. ..............................................................................................................................................................................

(ii) Great care is taken in selling Gasohol. What is the danger of making it too freely available?

om

......................................................................................................................................................................... [2]

......................................................................................................................................................................... [1] State another major use of ethanol.

e.c

(d)

ww w.c

he

ma

ctiv

......................................................................................................................................................................... [1]

TOTAL / 12

GCSE CHEMISTRY


QUESTIONSHEET 16

Complete the table showing the names, molecular formulae and structural formulae of three compounds obtained from crude oil.

name

molecular formula

butane

C4H10

structural formula

om

(a)

PRODUCTS FROM OIL

pentane

H

H

H

C

C

C

C

C

H

H

H

H

H

H

ctiv

H

[4]

he

ma

hexane

(b)

H

e.c

H

Butane is highly flammable. Suggest two precautions which must be taken when storing it.

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

Ethane boils at –88oC and ethene at –104oC. Why are they difficult to separate? ......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 17

The graph shows the percentage of North Sea crude oil which distils off during fractional distillation at different temperatures. Percentage of crude oil distilled

100 80 60 40

(a)

200 300 100 Distillation temperature (oC)

400

e.c

0

om

20

From the graph estimate the percentage which distils: (i)

below 20oC.

(ii) between 40oC and 75oC (petrol fraction).

ctiv

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1]

ma

(iii) between 75oC and 150oC (naphtha fraction).

......................................................................................................................................................................... [1] In what physical state would you expect the fraction below 20oC to be in?

he

(b)

......................................................................................................................................................................... [1] The table below gives the uses of the products from crude oil.

ww w.c

(c)

use

heating road transport generating electricity making chemicals

% of oil used 44 37 8

Calculate the percentage of crude oil used for making chemicals. ......................................................................................................................................................................... [1]

TOTAL / 5

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 18

Detergents, paints and inks are all made from the components of crude oil. (a)(i)

What is a detergent?

......................................................................................................................................................................... [1] (ii) Explain why it is important that detergents are biodegradable.

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

(b) (i)

e.c

......................................................................................................................................................................... [2]

Inks are often mixtures of different coloured dyes. What technique could you use to prove this?

ctiv

......................................................................................................................................................................... [1]

ma

Ben and Jessica used this technique to compare the inks from different pens. Their results are shown below.

BLUE

ORANGE

he

BLUE

ww w.c

YELLOW

YELLOW

RED

A

STARTING LINE (DRAWN IN PENCIL) B

(ii) Why did they draw the starting line in pencil? ......................................................................................................................................................................... [1] (iii) Which dye did the two inks both contain? ......................................................................................................................................................................... [1] (iv) Which colour was only found in ink B? ......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 19

(a)

The table shows some of the uses of plastics. Complete the table by filling in the best reason for each use from the list below. The first one has been done for you. REASONS - lightweight, does not conduct electricity, non-toxic, easily moulded, can be coloured, flexible. best reason does not conduct electricity

e.c

om

use coating for wires guttering carrier bags combs sandwich bags

[4]

ctiv

Crude oil, from which plastics are made, is first separated into fractions. Information about some of the fractions is given in the table. boiling range (oC) -160 to 40 40 to 80 80 to 150 150 to 240

fraction petroleum gas petrol naphtha kerosene (i)

number of carbon atoms 1 to 4 5 to 10 8 to 12 10 to 16

ma

(b)

State a use for kerosene.

he

......................................................................................................................................................................... [1]

ww w.c

(ii) In which fraction would this molecule be found?

H

H

H

H

H

H

H

C

C

C

C

C

C

H

H

H

H

H

H

H

......................................................................................................................................................................... [1] (iii) Propene has a boiling point of –47oC. In which fraction would propene be found? ......................................................................................................................................................................... [1]

TOTAL / 7

GCSE CHEMISTRY

PRODUCTS FROM OIL


QUESTIONSHEET 20

Some fizzy drinks bottles are made from plastics. There are a number of ways of disposing of waste plastic bottles. Some are shown in the table below.

(a)

method burn them with other household rubbish fill in quarries with household waste re-use the bottles make them into pellets of pure plastic

Which two of the options help to conserve oil reserves?

om

option A B C D

Describe environmental problems which could be caused by options A or B. (i)

Option A

ctiv

(b)

e.c

......................................................................................................................................................................... [1]

..............................................................................................................................................................................

(ii) Option B

ma

......................................................................................................................................................................... [2]

..............................................................................................................................................................................

In option C, the bottles would need to be sterilised before being re-used. Glass bottles are sterilised using superheated steam. Why might this be unsuitable for plastic bottles?

ww w.c

(c)

he

......................................................................................................................................................................... [2]

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

What could be done with heat produced in option A? ......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY

RATES OF REACTION


QUESTIONSHEET 1

Calcium carbonate reacts with dilute hydrochloric acid to produce the gas carbon dioxide. The table below gives the results from a reaction when 40 cm3 dilute hydrochloric acid was added to one marble chip (calcium carbonate) at room temperature of 20oC. The calcium carbonate was in excess. One of the results in the table is unreliable. 71.00

70.74

70.54

70.40

70.30

70.24

time (min)

0

1

2

3

4

5

70.20

6

7

70.20

70.20

8

9

On the grid below plot a graph of the results shown in the table above.

e.c

(i)

70.26

om

Mass of flask and contents (g)

[3]

ma

ctiv

Draw a smooth curve through the reliable points and label it A.

ww w.c

he

Mass of flask and contents (g)

70.00 0 Time (min)

(Continued...)

GCSE CHEMISTRY

RATES OF REACTIONS QUESTIONSHEET 1 CONTINUED

(ii) Sketch carefully on the grid the graph that would be obtained if: I.

the same reaction was carried out at a temperature of 50oC. Label this graph B.

II. when an identical piece of calcium carbonate was reacted with only 20 cm3 of the dilute acid. Label this graph C.

[2]

[2]

(iii) Explain your answer to part (ii) I, in terms of particle collision.

om

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

he

ma

ctiv

e.c

......................................................................................................................................................................... [3]

TOTAL / 10

GCSE CHEMISTRY

RATES OF REACTION


QUESTIONSHEET 2

Some chemical reactions may take place twice as quickly if their temperature is raised by 10oC. (a)

If a particular reaction takes 32 minutes at 20oC, how long will it take if the temperature is raised to 50oC? .............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

Plot a graph of temperature against time taken to complete the reaction.

[3]

(c)

ctiv ma

ww w.c

he

Temperature/ oC

e.c

(b)

om

......................................................................................................................................................................... [2]

Time / min

Explain why the line on your graph does not meet either axis. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 3

Carbonates react with acids to produce a salt, carbon dioxide and water. (a)

The equation describes the reaction between calcium carbonate and hydrochloric acid. CaCO3 (i)

+

2HCl

Æ

CaCl2

+

CO2

+

H2O

Add state symbols to complete the equation.

[1]

om

(ii) Name the salt produced in this reaction. ......................................................................................................................................................................... [1]

e.c

(iii) Use the relative atomic masses C =12, Ca = 40 and O=16 to calculate the relative formula mass of calcium carbonate. Show your working. ..............................................................................................................................................................................

(iv)

ctiv

......................................................................................................................................................................... [1] How much carbon dioxide can be produced from: A 100 g calcium carbonate?

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] B 1 g calcium carbonate?

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] A student wished to measure the production of carbon dioxide in the above reaction. She considered the two methods outlined in the diagram.

ww w.c

(b)

Method A

add 25 cm3 hydrochloric acid

weigh immediately

leave for 2 minutes

Method B boiling tube with 25 cm3 hydrochloric acid

1g calcium carbonate

weigh

pour acid into beaker, replace boiling tube in beaker

reweigh leave for 2 minutes

reweigh

(Continued...)

GCSE CHEMISTRY

RATES OF REACTION QUESTIONSHEET 3 CONTINUED

(i)

Before carrying out the experiment, she performed the calculation in part (a) (iv) B of this question. Suggest how this information could be of use to her.

.............................................................................................................................................................................. .............................................................................................................................................................................. ..............................................................................................................................................................................

om

......................................................................................................................................................................... [2] (ii) Explain why, of the two methods shown, method B would provide a more reliable estimate of the amount of carbon dioxide produced during the reaction.

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ctiv

..............................................................................................................................................................................

ww w.c

he

ma

......................................................................................................................................................................... [2]

TOTAL / 10

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 4

Raj’s chemistry teacher puts a beaker of sodium thiosulphate on the windowsill. Raj can clearly see a tree on the school field through the beaker. The teacher adds hydrochloric acid to the beaker. After 120 seconds Raj cannot see the tree although he is looking carefully. (a)

Explain why. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

om

The teacher repeats the experiment with three other classes. The tree disappears from view at different times. Time for tree to disappear in seconds 120 200 150

Class

ctiv

e.c

9X 9Y 9Z

The three experiments were identical except for the day on which they were done.

(i)

Which class did the experiment: on a warm spring day?

ma

(b)

......................................................................................................................................................................... [1]

he

(ii) during a summer heat wave?

......................................................................................................................................................................... [1]

ww w.c

(iii) on a January day when the school heating was not working well? ......................................................................................................................................................................... [1] The following year the local group of schools agree to do the same experiment on the same day under exactly the same conditions using the same chemicals. They look at objects that are the same distance away. The results are: -

School

St Peter’s St Paul’s St Mary’s

Time for tree to disappear in seconds 110 100 150

The teachers tested the chemicals used. They found that the sodium thiosulphate was of different concentration in each school. (c)(i)

Which school had the strongest solution?

......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY


(ii) Give reasons for your answer. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] Hanif decides to use an ultraviolet lamp and an electric motor powered by a photoelectric cell.

om

How could he use this equipment to measure the cloudiness of the liquid in a more objective way? Draw a diagram of how the equipment might be set up.

..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

ma

ctiv

..............................................................................................................................................................................

ww w.c

(d)

[4]

TOTAL / 12

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 5

Cotton is starched to make it easier to weave into denim cloth. Before the cloth is made up into clothing the starch is removed so that it can be more easily sewn. Denim from a newly woven roll is tested to find out the best conditions for the removal of starch using the biological catalyst amylase. A solution of amylase is made up and five equal pieces are cut from the roll of denim. Equal quantities of amylase are added to four of the five pieces in separate beakers. The beakers are kept at temperatures of 20oC, 40oC, 60oC and 80oC respectively for 15 minutes. Afterwards all five pieces are tested for starch. What is a catalyst?

om

(a) (i)

......................................................................................................................................................................... [2]

e.c

(ii) What is the name given to biological catalysts?

......................................................................................................................................................................... [1] Which of the cotton samples would you expect to contain the most starch?

ctiv

(b) (i)

......................................................................................................................................................................... [1] (ii) Explain your answer.

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

he

......................................................................................................................................................................... [3] (iii) Which sample would you expect to contain the least starch?

ww w.c

......................................................................................................................................................................... [1] (iv) Explain your answer.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (v) What chemical is most often used to detect starch? ......................................................................................................................................................................... [1]

TOTAL / 11

GCSE CHEMISTRY

RATES OF REACTION


QUESTIONSHEET 6

The following equation shows what happens when magnesium ribbon reacts with hydrochloric acid. Mg(s) + 2HCl(aq) Æ MgCl2(aq) + H2(g) (a)

What would you see happening to the magnesium ? ......................................................................................................................................................................... [1] 40 cm3 of gas is collected in 10 seconds. What is the rate of reaction?

om

(b)

......................................................................................................................................................................... [1] How would the rate compare if you used very dilute hydrochloric acid? Explain why.

e.c

(c)

..............................................................................................................................................................................

(d)

ctiv

......................................................................................................................................................................... [2] State two ways in which the reaction could be speeded up besides changing the concentration of hydrochloric acid.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Calculate how many moles of hydrogen gas are collected.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

(e)

......................................................................................................................................................................... [2] [24 dm3 is the volume of 1 mole of gas at room temperature]

TOTAL / 8

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 7

When 0.15 M sodium thiosulphate solution (Na2S2O3(aq)) is added to hydrochloric acid, sulphur is formed. (a)

What would you observe during the reaction? ......................................................................................................................................................................... [1]

(b)

What other products are formed? ..............................................................................................................................................................................

om

......................................................................................................................................................................... [2] (c)

Apart from heating it, how else could you speed up the reaction? How would this work?

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

30 20 5 27

20 30 5 56

10 40 5 3 min [3]

he

Plot a graph of the results

40 10 5 13

ww w.c

(d) (i)

50 0 5 5

ma

Na2S2O3(aq) Volume H2O(l) (cm3) HCl(aq) Reaction Time (s)

ctiv

The following results table was obtained by mixing various amounts of sodium thiosulphate solution, water and 1 M hydrochloric acid.

(Continued...)

GCSE CHEMISTRY


(ii) Which variable are you testing? ......................................................................................................................................................................... [1] (iii) Why is the volume of acid kept the same? ......................................................................................................................................................................... [1] (iv) What would you observe during the reaction?

ww w.c

he

ma

ctiv

e.c

om

......................................................................................................................................................................... [1]

TOTAL / 11

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 8

Yoghurt is made from milk. Yoghurt contains lactic acid formed from lactose, the sugar present in milk. Recently a new type of yoghurt has appeared in the shops in which bacteria from Russian cosmonauts has been used in the process. (a)

Describe a test to show that an acid is formed when milk is turned into yoghurt. State the result of the test. ..............................................................................................................................................................................

(b)

om

......................................................................................................................................................................... [2] For all practical purposes, a solution of lactose does not change into lactic acid. Adding bacteria increases the rate of reaction. What is meant by the phrase ‘rate of reaction’?

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Why does the addition of bacteria have this effect?

ctiv

(c)

......................................................................................................................................................................... [1] Describe or draw diagrams to show what is happening to individual molecules of lactose in the reaction to form lactic acid molecules in yoghurt.

ma

(d)

..............................................................................................................................................................................

(e)

ww w.c

he

..............................................................................................................................................................................

[3]

After a while the rate of formation of lactic acid decreases. Why is this? ......................................................................................................................................................................... [1]

(f)

The yoghurt – milk mixture is heated to about 70oC.What effect does this have on the rate of the production of lactic acid? Explain your answer. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 11

GCSE CHEMISTRY

RATES OF REACTION QUESTIONSHEET 9


2 10

4 16

6 20

8 -

[3]

he

ma

ctiv

Plot a graph of the results.

10 22

ww w.c

(a)

0 0

e.c

Time (s) Volume (cm3)

om

The apparatus shown can be used to collect gas formed by reacting magnesium and sulphuric acid. The following table of data was collected.

(Continued...)

GCSE CHEMISTRY

RATES OF REACTIONS QUESTIONSHEET 9 CONTINUED

(b)

One experimental result was missed. (i)

What value could it have?

......................................................................................................................................................................... [1] (ii) Why is it easy to miss results like this during experiments?

(c) (i)

om

......................................................................................................................................................................... [1] Which gas is formed in the reaction ?

......................................................................................................................................................................... [1]

e.c

(ii) How could you test for this gas?

ww w.c

he

ma

ctiv

......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY



Some cars are fitted with catalytic converters to remove harmful substances from exhaust gases.

om

The platinum catalyst is coated onto a honeycombed ceramic support. It works best when the engine has warmed up. (a)(i)

Explain why a honeycombed support is better than a solid one.

e.c

......................................................................................................................................................................... [1] (ii) Explain why the catalyst works better when the engine is warm.

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Heavy metals may stick to the catalyst and prevent it from working. The catalyst is said to be poisoned.

(i)

ma

(b)

Explain how catalysts work and how poisoning with heavy metals prevents this.

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [3] (ii) Why should the owners of cars with catalytic converters always use unleaded petrol? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 8

GCSE CHEMISTRY

RATES OF REACTIONS QUESTIONSHEET 11


Hydrogen peroxide (H2O2) breaks down slowly to form water and oxygen. (a)

Write a balanced symbol equation for the reaction. ......................................................................................................................................................................... [2] The reaction can be greatly speeded up by a catalyst. (i)

Name a possible catalyst.

om

(b)

......................................................................................................................................................................... [1] (ii) How does the catalyst work?

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ctiv

(iii) How could you show that the catalyst was unchanged at the end of the reaction? ..............................................................................................................................................................................

ww w.c

he

ma

......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY



om

The diagram shows a flask of zinc metal reacting with hydrochloric acid on a chemical balance.

ctiv

e.c

150 g

(a)

How could this apparatus be used to measure the speed of the reaction? ..............................................................................................................................................................................

(b)

(i)

ma

......................................................................................................................................................................... [2] What is the gas being produced?

(ii)

he

......................................................................................................................................................................... [1] How would you test the gas to identify it?

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii)

Write an equation for the reaction which is taking place.

......................................................................................................................................................................... [2] (c)

How would you expect the results to change if:

(i)

the temperature was increased?

......................................................................................................................................................................... [1] (ii) the zinc was ground into a fine powder? ......................................................................................................................................................................... [1] (iii) the concentration of the hydrochloric acid was increased? ......................................................................................................................................................................... [1] TOTAL / 10

GCSE CHEMISTRY


RATES OF REACTIONS

QUESTIONSHEET 13

Chemical reactions are caused when molecules of different chemicals collide. (a)

Describe the effect of increasing the pressure of two gases on the rate of reaction using this collision theory. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] Cornflour is used on the production line in some sweet factories. It is carried in the air. Special precautions have to be taken to remove the cornflour from the air as a fire hazard. Why is this fine powder a fire hazard?

om

(b)

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] 10 g of magnesium ribbon burns up in 1 minute. How fast would you expect 10 g of magnesium powder to burn?

ctiv

(c)

......................................................................................................................................................................... [1] Why is heat often provided as a means of speeding up chemical reactions?

ma

(d)

..............................................................................................................................................................................

Why does food not keep for ever in a freezer?

..............................................................................................................................................................................

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(e)

he

......................................................................................................................................................................... [2]

......................................................................................................................................................................... [2]

TOTAL / 9

GCSE CHEMISTRY


RATES OF REACTION

QUESTIONSHEET 14

A research laboratory is investigating the effectiveness of various catalysts for the reduction of pollution in petrol powered car exhausts. They obtain the following results using their own ‘pollution units’, P. [10 P = 10 pollution units.]

Carbon monoxide P 700 150 250 75

Oxides of nitrogen P 500 150 300 90

om

None A B C

Petrol P 100 30 50 10

e.c

Catalyst

In his lab notebook the scientist uses the abbreviations ‘CO’, ‘NOx’ and ‘CH’. What do these abbreviations stand for?

ctiv

(a)

..............................................................................................................................................................................

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [3] (b) (i)

Which catalyst is most effective at reducing total pollution?

he

......................................................................................................................................................................... [1]

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(ii) Which is the largest pollutant in the exhaust before a catalyst is used? ......................................................................................................................................................................... [1] (iii) Which is the largest pollutant in the exhaust from the most effective catalyst? ......................................................................................................................................................................... [1]

TOTAL / 6

GCSE CHEMISTRY

RATES OF REACTIONS

QUESTIONSHEET 15


Hydrogen peroxide and a catalyst are mixed in the apparatus below. The hydrogen peroxide decomposes into water and oxygen.

om

chemicals A or B added here

The results obtained are represented on the graph below

e.c

heat energy

ctiv

no catalyst

90

time in seconds

On the same axes, draw a line to represent the volume of oxygen produced when the reaction is repeated with 5 g of a granulated catalyst in the flask. Label this (i).

ww w.c

(a) (i)

60

he

30

ma

volume of gas

(ii) On the same axes, draw a line to represent the volume of oxygen produced when the reaction is repeated with 5 g of a powdered catalyst in the flask. Label this (ii). (b)

[1]

[1]

John measures the volume of gas produced when 5 g of two chemicals X and Y are added to hydrogen peroxide under identical conditions. His results for this experiment look like this.

volume of gas

Y

X

30

60

90

time in seconds

He claims that they show that Y is a better catalyst than X. John’s partner Steven does not agree.

(Continued...)

GCSE CHEMISTRY


What does Steven find wrong with the results? .............................................................................................................................................................................. ......................................................................................................................................................................... [2] After the experiment Steven recovers 5 g of X and 1 g of Y from the two experiments. He claims that this shows that John is wrong.

om

Why might he think this? ..............................................................................................................................................................................

he

ma

ctiv

e.c

......................................................................................................................................................................... [2]

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(c)

TOTAL / 8

GCSE CHEMISTRY

RATES OF REACTIONS QUESTIONSHEET 16


200 cm3 of hydrogen peroxide solution are warmed in a flask. The volume of gas produced is measured using a syringe. After 30 seconds 5 g of a chemical A is added to the hydrogen peroxide and the volume of gas continues to be measured. The experiment is then repeated but this time another chemical, B, replaces A. A third experiment has chemical B replaced by chemical C.

om

chemicals A, B or C added here

e.c

heat energy

C

A

B

30

(a)

ma

volume of gas

ctiv

The graph below shows the volume of gas produced over time when the chemicals A, B and C are added.

time in seconds

60

What is the formula of hydrogen peroxide?

(b)

What is the gas produced?

he

......................................................................................................................................................................... [1]

(c) (i)

ww w.c

......................................................................................................................................................................... [1] What is a catalyst?

......................................................................................................................................................................... [2] (ii) Which of the three chemicals A, B and C is not a catalyst? (Give a reason for your choice) .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) Which of the three chemicals is the best catalyst? (Give a reason for your answer) .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

How much of the compounds B and C should be recovered from the flasks after the experiment? ......................................................................................................................................................................... [1] TOTAL / 9

GCSE CHEMISTRY

RATES OF REACTION


QUESTIONSHEET 17

(a)

List three ways of increasing the rate of a chemical reaction. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] Explain why it is not possible to light a dead tree with a match.

om

(b)

.............................................................................................................................................................................. ..............................................................................................................................................................................

Why is it difficult to light coal, but coal dust in mines can cause explosions?

ctiv

..............................................................................................................................................................................

he

ma

......................................................................................................................................................................... [2]

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(c)

e.c

......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 18

The graph below shows the volume of gas produced in an experiment over a period of time. 70 E

D

60

C

om

40 30 20

B

e.c

Volume of gas/ cm3

50

10 0

10

0

20

30

40

50

60 Time/s

70

80

90

100

110

120

Write down the letter which represents: the point at which the reaction has first stopped.

ma

(a) (i)

ctiv

A

......................................................................................................................................................................... [1]

he

(ii) the point at which the reaction is going at its fastest.

......................................................................................................................................................................... [1] Use the graph to estimate: the volume of gas produced after 60 seconds.

ww w.c

(b) (i)

......................................................................................................................................................................... [1] (ii) the time taken for 30 cm3 of gas to be collected. ......................................................................................................................................................................... [1] (c)

If the experiment was repeated with a catalyst present, how much gas would you expect to collect in total? ......................................................................................................................................................................... [1]

(d)

(i)

If the experiment in (c) was repeated with twice as much catalyst, how much gas would you expect to collect in total?

......................................................................................................................................................................... [1] (ii)

Would the speed of collection of the gas be faster, slower or the same as in experiment (c)?

......................................................................................................................................................................... [1] TOTAL / 7

GCSE CHEMISTRY

RATES OF REACTION


QUESTIONSHEET 19

Rates of reactions can be measured in a number of ways. (a)

Name two pieces of apparatus which could be used to measure volumes of gases.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

om

(b)(i) If you were timing how long magnesium took to dissolve in different concentrations of acid, what controls would you use to make sure the experiment was fair? ..............................................................................................................................................................................

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [3]

Stop clock

alarm clock

egg timer

[1]

ma

Which of the following pieces of apparatus would be most suitable for weighing a marble chip? (Underline the correct answer) spring balance

he

balance reading to 4 decimal places balance reading to 2 decimal places balance reading in whole grams

[1]

ww w.c

(c)

kitchen clock

ctiv

(ii) Which of the following would be best for timing the reactions? (Underline the correct answer)

TOTAL / 7

GCSE CHEMISTRY

RATES OF REACTIONS


QUESTIONSHEET 20

Complete the following sentences. Heat energy is measured in _______.

(ii)

One thousand of these is called a _______.

(iii)

A reaction which gives out heat is described as _______.

(iv)

A reaction which takes in heat is described as _______.

(v)

A _________ will speed up a chemical reaction without being permanently used up.

(vi)

Reactions involving gases can be speeded up using _________ pressure.

om

(i)

e.c

(vii) Powders have a greater ______ _______ than lumps of a solid. (viii) Curtains fading and _______ are examples of reactions which

he

ma

ctiv

are triggered by _______.

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(ix)

TOTAL / 9

GCSE CHEMISTRY

REACTIONS & FORMULAE


QUESTIONSHEET 1

Look at the following section of the periodic table. 1

2

3

4

5

66

7

0 He

H Li

Be

B

C

N

O

F

Ne

Na

Mg

Al

Si

P

S

Cl

Ar

K

Ca

Ga

Ge

As

Se

Br

Kr

Ti

V

Cr

Mn

Fe

Co

Ni

Cu

Use only the elements shown to answer the following questions.

When metals react with non-metals they form ionic compounds.

(i)

How do metal atoms form ions?

e.c

(a)

Zn

om

Sc

......................................................................................................................................................................... [1]

ctiv

(ii) Write the symbol of a metal that forms +1 ions.

......................................................................................................................................................................... [1]

(i)

Write down the formulae of: an aluminium ion.

ma

(b)

(ii) a chloride ion.

he

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1]

ww w.c

(iii) aluminium chloride.

......................................................................................................................................................................... [1] (c)

When non-metals react with non-metals they form molecules.

(i)

What type of bonding is found in molecules?

......................................................................................................................................................................... [1] (ii) Tetrachlormethane is a compound of carbon and chlorine. Write down the formula of tetrachloromethane. ......................................................................................................................................................................... [1] (iii) Ammonia exists as molecules. Draw a dot and cross diagram to show the bonding in ammonia.

[2] TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 2

When calcium carbonate (limestone) is heated it produces calcium oxide and carbon dioxide. (i)

Complete the following equation CaCO3

→

CaO

+

________

[1]

(ii) What name is given to this type of reaction? ......................................................................................................................................................................... [1] Calculate the relative molecular mass of calcium carbonate. (relative atomic masses: C=12, O=16, Ca=40)

om

(b)(i)

......................................................................................................................................................................... [1]

e.c

(ii) How many tonnes of calcium carbonate are needed to produce 280 tonnes of calcium oxide? ..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

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he

ma

......................................................................................................................................................................... [3]

TOTAL / 6

GCSE CHEMISTRY



QUESTIONSHEET 3

(a)

When magnesium burns in oxygen it produces magnesium oxide. Balance the following symbol equation. __Mg(s)

+

O2(g)

→

__MgO(s)

[1]

om

(b) Alison carefully reacted some magnesium with oxygen using the equipment below. She made sure that all the magnesium had reacted. tongs

e.c

lid

heat

ma

Here are the results of Alison’s experiment.

ctiv

crucible coil of magnesium ribbon pipeclay triangle

= 40.1 g = 44.9 g = 48.1 g

he

mass of crucible + lid mass of crucible + lid + magnesium mass of crucible + lid + magnesium oxide

ww w.c

Use Alison’s results to calculate the empirical formula of magnesium oxide. (relative atomic masses: O = 16, Mg = 24) .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [6]

TOTAL / 7

GCSE CHEMISTRY



QUESTIONSHEET 4

The diagram shows an experiment to investigate the effect of heat on copper(II) sulphate crystals.

heat

tube A

blue copper(ll) sulphate crystals

tube B

om

cold water

(a)(i)

e.c

colourless liquid

Why is cold water used in the beaker?

ctiv

......................................................................................................................................................................... [1] (ii) How could you identify the colourless liquid in tube B as water? ..............................................................................................................................................................................

(b)

ma

......................................................................................................................................................................... [1] When 2.5 g of blue copper(II) sulphate crystals were heated, 1.6 g of white solid were left in tube A. Calculate the mass of water driven off in the experiment.

he

(i)

......................................................................................................................................................................... [1]

ww w.c

(ii) Calculate the percentage of water driven off.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

The equation represents the change taking place on heating blue copper(II) sulphate crystals. CuSO4.5H2O ∏

CuSO4

+

5H2O

(i) What type of change is taking place? ......................................................................................................................................................................... [1] (ii) Write an equation to represent what happens when water is added to white copper(II) sulphate. ......................................................................................................................................................................... [1] (ii) What symbol should be used instead of the arrow in the first equation? ......................................................................................................................................................................... [1] TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 5

Nitrogen is an important element to help plants to grow. Artificial fertilisers contain compounds of nitrogen. Two such compounds are sodium nitrate (NaNO3), ammonium nitrate (NH4NO3). (a)

Calculate the relative molecular masses of each of these compounds. (Relative atomic masses: H = 1, C = 12, N = 14, O = 16, Na = 23)

(i)

sodium nitrate.

om

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

e.c

(ii) ammonium nitrate.

..............................................................................................................................................................................

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] Calculate the percentage of nitrogen in: (i)

sodium nitrate.

ma

(b)

..............................................................................................................................................................................

he

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [2] (ii) ammonium nitrate.

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

Which of them would be best for a farmer to use? ......................................................................................................................................................................... [1]

(d)

Ammonia, NH3 has 82.4% of nitrogen in it. Give two reasons why it would be unsuitable for use as a fertiliser.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 6

(a)

Calculate the empirical formulae of the following compounds. (Relative atomic masses: H=1, C=12, N=14, O=16, S=32, K=39, Fe=56)

(i)

a compound of 3.5 g nitrogen and 4 g oxygen.

.............................................................................................................................................................................. ..............................................................................................................................................................................

om

......................................................................................................................................................................... [2] (ii) a compound of 50% oxygen and 50% sulphur.

e.c

.............................................................................................................................................................................. ..............................................................................................................................................................................

ctiv

......................................................................................................................................................................... [2] (iii) a compound of 39% potassium, 1% hydrogen, 12% carbon and 48% oxygen. ..............................................................................................................................................................................

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

he

(iv) 16.0 g of an oxide of iron formed from 11.2 g iron.

..............................................................................................................................................................................

ww w.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [3] (b)

Find (i) the empirical formula and (ii) the molecular formula of a compound containing 4.04% hydrogen, 24.24% carbon and 71.72% chlorine, given the following information: relative atomic masses: H=1, C=12, Cl=35.5 relative molecular mass of the compound = 99 (i) .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] (ii) .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 14

GCSE CHEMISTRY



QUESTIONSHEET 7

A chemist finds a compound in an unlabelled bottle. He carries out a number of experiments on it. Here are his results. colour heat add dilute hydrochloric acid heat and pass hydrogen over it Identify the black solid.

om

(a)

black no change solution of green salt brown solid, gas which condenses to colourless liquid

......................................................................................................................................................................... [1] Identify the green salt.

e.c

(b)(i)

......................................................................................................................................................................... [1]

ctiv

(ii) What products would be formed when a solution of the green salt is electrolysed? .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

(iii) How can the gas produced during electrolysis be identified by a chemical test? ..............................................................................................................................................................................

(c)(i)

he

......................................................................................................................................................................... [2] Name the brown solid produced in the fourth test.

ww w.c

......................................................................................................................................................................... [1] (ii) Name the liquid which condenses in the fourth test. ......................................................................................................................................................................... [1] (iii) Write an equation for the reaction.

......................................................................................................................................................................... [1] (iv) What is the role of hydrogen in this reaction? ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 8

Barium chloride contains water of crystallisation (BaCl2.xH2O). Some barium chloride was heated in a basin. The results are shown below. mass of empty basin = 117.8 g mass of basin plus BaCl2.xH2O = 125.9 g mass of basin plus BaCl2 after heating = 124.7 g (a)(i)

Why was the empty basin weighed?

om

......................................................................................................................................................................... [1] (ii) Calculate the mass of BaCl2.xH2O.

e.c

......................................................................................................................................................................... [1] (iii) Calculate the mass of BaCl2 after heating. ......................................................................................................................................................................... [1] (iv) Calculate the mass of water lost.

ctiv

......................................................................................................................................................................... [1] (v) Calculate the percentage of water in the BaCl2.xH2O. ..............................................................................................................................................................................

(b)

ma

......................................................................................................................................................................... [2] What could be done to ensure that all the water had been lost?

he

.............................................................................................................................................................................. ..............................................................................................................................................................................

(c)

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......................................................................................................................................................................... [3] Calculate the relative molecular masses of: (i) BaCl2 .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (ii) H2O .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (Relative atomic masses: H = 1, O = 16, Cl = 35.5, Ba = 137) (d)

Use your previous answers to determine the value of x in BaCl2.xH2O. .............................................................................................................................................................................. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] TOTAL / 14

GCSE CHEMISTRY

REACTIONS & FORMULAE QUESTIONSHEET 9


The following words describe ten different types of chemical reaction.

decomposition

precipitation

combustion

oxidation

reduction

reversible

exothermic

endothermic

displacement

neutralisation

om

Write the correct word after each of the following descriptions of chemical reactions. (a) two solutions are mixed together and form an insoluble product

e.c

......................................................................................................................................................................... [1] (b) a reaction in which oxygen is removed from one of the reactants

ctiv

......................................................................................................................................................................... [1] (c) a reaction which takes in heat from the surroundings

......................................................................................................................................................................... [1]

ma

(d) a reaction where products can form the original reactants

......................................................................................................................................................................... [1]

he

(e) a single substance breaks down into two or more simpler ones ......................................................................................................................................................................... [1] a substance loses electrons

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(f)

......................................................................................................................................................................... [1] (g) one element takes the place of another in a compound ......................................................................................................................................................................... [1] (h) a substance burns in oxygen

......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY



When calcium oxide reacts with water it forms calcium hydroxide (slaked lime). The reaction is exothermic. (a) Explain what is meant by an ‘exothermic reaction’. ......................................................................................................................................................................... [1]

om

(b) The formula for a calcium ion is Ca2+ and that of a hydroxide ion is OH-. Write down the formula for calcium hydroxide. ......................................................................................................................................................................... [1] (c) Write down one use of slaked lime.

e.c

......................................................................................................................................................................... [1]

ctiv

(d) When slaked lime is dissolved in water, it produces a solution known as limewater. It is possible to make a small amount of calcium carbonate from limewater. Explain how this can be done. ......................................................................................................................................................................... [1]

ma

(e) How can calcium carbonate be converted into quicklime?

......................................................................................................................................................................... [1]

he

(f) The reactions described above are often put together in a diagram called the calcium cycle. Explain the word “cycle” in this context. ..............................................................................................................................................................................

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......................................................................................................................................................................... [2]

TOTAL / 7

GCSE CHEMISTRY



Solutions of different halogens were mixed with solutions of halide salts. The mixtures were shaken with some organic solvent. Halogens dissolve better in the solvent than in water and give distinctive colours. (chlorine - green, bromine - orange, iodine - violet) Here are the results of some experiments. halogen added

halide salt

A B C D E F

chlorine chlorine bromine bromine iodine iodine

potassium bromide potassium iodide potassium chloride potassium iodide potassium chloride potassium bromide

colour after shaking orange violet orange violet violet violet

e.c

om

experiment

ctiv

(a) What type of reaction is taking place?

......................................................................................................................................................................... [1] (b) In which experiments are no reactions taking place?

ma

......................................................................................................................................................................... [3] (c) Write a word equation for experiment A.

he

......................................................................................................................................................................... [1]

Write a symbol equation for experiment A.

[2]

(e)

What do the experiments tell you about the relative reactivities of chlorine, bromine and iodide?

ww w.c

(d)

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (f)

How would you expect fluorine to react with potassium chloride?

......................................................................................................................................................................... [1] (g) How would you expect chlorine to react with potassium fluoride? ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 12

The table below gives information about the solubilities of a number of salts. sodium soluble soluble

potassium soluble soluble

lead insoluble insoluble

barium soluble insoluble

nitrate carbonate

soluble soluble

soluble soluble

soluble insoluble

soluble insoluble

calcium soluble slightly soluble soluble insoluble

om

chloride sulphate

(a)

What can you say about the solubility of sodium and potassium salts?

(b)

What can you say about the solubility of nitrates?

e.c

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] What can you say about the solubility of lead salts?

ctiv

(c)

......................................................................................................................................................................... [2] Predict the products of the following reactions, underlining any precipitates. (i)

ma

(d)

sodium carbonate solution with lead nitrate solution

he

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ww w.c

(ii) calcium chloride solution with potassium nitrate solution .............................................................................................................................................................................. ......................................................................................................................................................................... [1] (iii) barium chloride solution with sodium sulphate solution .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (e)

Barium salts are poisonous, yet some X-ray patients have to drink barium sulphate. Explain why they can do this without harming themselves. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

TOTAL / 11

GCSE CHEMISTRY



Five students wanted to find out what would happen when a certain compound was heated. They found that a gas was given off, so they measured the mass of the gas lost. Their results are shown below. student loss in mass (g) volume of gas (cm3)

1 0.032 24

2 0.06 45

3 0.083 62

5 0.107 80

[4]

ctiv ma he ww w.c

loss in mass (g)

e.c

om

(a) Plot the results on the graph.

4 0.09 75

volume of gas (cm3)

(Continued...)

GCSE CHEMISTRY

REACTIONS & FORMULAE QUESTIONSHEET 13 CONTINUED

(b)

Which student’s result is incorrect? ......................................................................................................................................................................... [1]

(c)

Use your graph to estimate: (i)

the volume of 0.05 g of the gas.

......................................................................................................................................................................... [1]

The gas given off is oxygen. (i)

[1]

How can the results of the experiment be used to confirm this?

e.c

(d)

the mass of 15 cm3 of the gas.

om

(ii)

..............................................................................................................................................................................

ctiv

......................................................................................................................................................................... [2] (ii) Describe a chemical test that can confirm the identity of the gas.

ma

..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [2]

TOTAL / 11

GCSE CHEMISTRY


Medium Demand Questions Study the diagram below. tube A

tube B

tube D

tube C

om

oil

cotton wool

(a) (i)

boiled and cooled water

In which two tubes will the steel go rusty?

calcium chloride

e.c

distilled water

salt solution

ctiv

......................................................................................................................................................................... [1] (ii) Why does the steel not rust in the other two tubes?

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] In which tube will the rusting occur fastest? Explain your answer.

he

(b)

..............................................................................................................................................................................

ww w.c

......................................................................................................................................................................... [2]

(c)

Explain how ships and piers are prevented from rusting. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

(d)

State how each of the following is prevented from rusting. (i)

cutlery

......................................................................................................................................................................... [1] (ii) car bodies ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



Zinc metal can be extracted from the mineral zinc blende (zinc sulphide) Stage 1 - zinc blende heated in air to produce zinc oxide. Stage 2 - zinc oxide reacted with sulphuric acid to make a solution containing zinc ions. Stage 3 - zinc metal is obtained by electrolysis of the solution. The zinc extracted is used to coat other metals and in alloys. (a)

Suggest two advantages of alloys over pure metals.

om

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] Name the metal that zinc is often used to protect.

e.c

(b) (i)

......................................................................................................................................................................... [1]

ctiv

(ii) What is the process of covering a metal with zinc called?

......................................................................................................................................................................... [1] (c) (i)

Apart from zinc oxide, what other product is formed when zinc blende is heated in air?

ma

......................................................................................................................................................................... [1]

he

(ii) The formula of zinc oxide is ZnO. The formula of an oxide ion is O2 . What is the formula of a zinc ion?

......................................................................................................................................................................... [1] What type of reaction occurs when zinc oxide reacts with sulphuric acid?

ww w.c

(d)

......................................................................................................................................................................... [1] (e)

Zinc can also be extracted from zinc oxide by heating it with coke. (i)

What is the main element in coke?

......................................................................................................................................................................... [1] (ii) Write an equation for the reaction between zinc oxide and coke. ......................................................................................................................................................................... [1] (iii) What type of reaction involves the removal of oxygen? ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY



The key below is used to identify five carbonates and a hydrogencarbonate. Does it dissolve in water?

No

Yes Does it give off carbon dioxide when heated?

Is it green? Yes No sodium carbonate

Yes

No

copper carbonate

ammonium carbonate

No sodium hydrogencarbonate

magnesium carbonate

Yes

calcium carbonate

Which soluble compound gives off carbon dioxide, but gives no smell?

ctiv

(a) (i)

No

e.c

Yes

om

Does it give a red flame test?

Does it smell of ammonia when heated?

......................................................................................................................................................................... [1] (ii) What type of substance will react with any carbonate or hydrogencarbonate to produce carbon dioxide?

ma

......................................................................................................................................................................... [1] (iii) Only one carbonate in the key produces no carbon dioxide when heated. Which one?

Tablets for upset stomachs often contain citric acid and magnesium carbonate. Describe and explain what happens when these tablets are added to water.

ww w.c

(b)

he

......................................................................................................................................................................... [1]

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (c)

A teaspoon of sodium hydrogencarbonate is added when making gingerbread. (i) What is the purpose of the sodium hydrogencarbonate? .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Why would sodium carbonate be unsuitable for this purpose? ......................................................................................................................................................................... [1]

TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 17

Quicklime, CaO, is made by heating limestone, CaCO3, in a rotating kiln. Limestone is added at the top of the kiln. Turning the kiln lets the limestone move slowly to the bottom as it is heated. Quicklime is formed and is taken from the bottom. (a)

Give the chemical name for: (i)

quicklime

om

......................................................................................................................................................................... [1] (ii) limestone

(b)

e.c

......................................................................................................................................................................... [1] Heat is required for the reaction to take place. What name is given to reactions which take in heat?

(c)

ctiv

......................................................................................................................................................................... [1] James investigated this reaction. He heated a piece of limestone on the edge of a gauze. Describe what he saw.

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

Before the rotating kiln was invented, each batch of limestone had to be heated separately. Suggest one advantage that the rotating kiln has over the older method.

ww w.c

(d)

he

......................................................................................................................................................................... [2]

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] (e)

There are proposals to extend a limestone quarry. (i) Give two arguments that the quarry owners could use in favour of the proposed extension. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Give two arguments that those against the extension could use. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 10

GCSE CHEMISTRY



QUESTIONSHEET 18

(a)

Some students decided to investigate the chemistry of seashells. They started by adding hydrochloric acid to some pieces of seashell. The mixture fizzed. They decided to find out if the gas was carbon dioxide. (i)

Complete the diagram below to show how they could do this.

om

hydrochloric acid

[3]

What result would they see if the gas was carbon dioxide?

ctiv

(ii)

e.c

sea shells

......................................................................................................................................................................... [2]

substance sodium chloride potassium chloride calcium chloride copper chloride

colour of flame yellow pink red green

Why is copper wire not used for the test?

ww w.c

(i)

ma

They then heated a small piece of shell in a flame. Different substances give different colours when put in a flame.

he

(b)

......................................................................................................................................................................... [1] (ii) How is the test wire cleaned between each test? ......................................................................................................................................................................... [1] The shells turned the flame a red colour. (iii) Which metal is in the seashells? ......................................................................................................................................................................... [1] (c)

Use the results of the two tests to select the chemical name of the substance from which seashells are made from the list below. sodium chloride

sodium carbonate

calcium carbonate

calcium chloride

......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY



QUESTIONSHEET 19

A

B

Ethanol C2H5OH

Kalium hydrogen sulfat KHSO4

D

C

Which bottle contains a potassium compound?

ma

(a)

e.c

Phosphorsaure H3PO4

ctiv

Zinc Zn

om

Some bottles of chemicals were imported from Germany. Their labels are in German.

......................................................................................................................................................................... [1] (b) (i)

Which bottle contains an element?

he

......................................................................................................................................................................... [1]

ww w.c

(ii) What gas is formed when this element is added to dilute sulphuric acid? ......................................................................................................................................................................... [1] (c)

Which bottle contains a flammable substance? ......................................................................................................................................................................... [1]

(d)(i) Which bottle contains a compound of four elements? ......................................................................................................................................................................... [1] (ii) What does the hazard label on this bottle mean? ......................................................................................................................................................................... [1] (e)

The gas, hydrogen, is known in German as “Wasserstoff”. Wasser means water. Suggest an explanation for the name. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 8

GCSE CHEMISTRY



QUESTIONSHEET 20

(a)

The diagram shows a cross section through a type of blast furnace, which was used in the Iron Age.

IRON +CHARCOAL

om

CHARCOAL

IRON FORMED HERE

e.c

AIR BLASTED HERE

(i)

ctiv

CLAY

The charcoal is the fuel for the furnace. Charcoal is mainly carbon. Write an equation for the burning of charcoal in a plentiful supply of air.

ma

......................................................................................................................................................................... [1] (ii) Some carbon monoxide may also be formed. Why is this undesirable?

The iron ore is reduced to iron when the furnace gets hot enough. (i)

What is meant by ‘reduced’ in this reaction?

ww w.c

(b)

he

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] (ii) Name a substance that is oxidised in the process. ......................................................................................................................................................................... [1] (c)

When the furnace was opened, the clay had changed. List three of the changes to the clay. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 7

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 1

The boxes represent particles of different gases. One box shows the particles of elements in group 0 (group 8).

A

D

What name is given to group 0 (8) elements?

om

(a) (i)

C

B

......................................................................................................................................................................... [1] (ii) Name two elements from group 0.

(b) (i)

e.c

......................................................................................................................................................................... [2] Which box best represents particles from group 0 elements?

(ii) Explain the reason for your answer.

ctiv

......................................................................................................................................................................... [1]

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] A lighted splint is put into a gas jar of helium. What would happen?

he

(c)

......................................................................................................................................................................... [1] Some properties of elements change as you go down their group in the periodic table. For each property listed below, comment on if and how it changes as you go down group 0. (i)

reactivity

ww w.c

(d)

......................................................................................................................................................................... [1] (ii) density

......................................................................................................................................................................... [1] (iii) metal or non-metal

......................................................................................................................................................................... [1] (e)

Which would be the best method to distinguish between different samples of group 0 gases? Choose from the list below: (i) (ii) (iii) (iv)

shake the sample with water and add an indicator, do a flame test, put a lighted splint into a sample of each gas, measure the density of each.

......................................................................................................................................................................... [1] TOTAL / 10

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 2

The diagram represents a sodium atom and a sodium ion.

x x

x xx x x xx

x x

x x

x x

x xx

B

A

Which diagram represents the sodium atom?

om

(a) (i)

xx x

......................................................................................................................................................................... [1] (ii) Give reasons for your choice.

e.c

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) Sodium is in group 1 of the periodic table. How can you tell this from its electron structure?

(b) (i)

ctiv

......................................................................................................................................................................... [1] What is an ion?

......................................................................................................................................................................... [1]

K

K+

ma

(ii) Potassium is also in group 1 of the periodic table. What is the symbol for the potassium ion? Choose from: K2+

K-

K2-

he

......................................................................................................................................................................... [1] (c)

Group 1 elements are stored in oil. Suggest the reason for this.

ww w.c

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d)

A small piece of potassium is taken out of its bottle and cut. The surface is silver coloured and shiny, but after a few minutes it looked dull and white. A chemical reaction had taken place. (i)

With what had the potassium reacted?

......................................................................................................................................................................... [1] (ii) What is the name of the substance formed on the outside of potassium? ......................................................................................................................................................................... [1] (iii) Write a word equation for the reaction. ......................................................................................................................................................................... [1] (iv) Write a balanced symbol equation for this reaction. ......................................................................................................................................................................... [2] TOTAL / 13

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 3

(a) (i)

Write a word equation for the reaction.

om

Lithium (Li) can be burnt in chlorine (C12) to give lithium chloride.

......................................................................................................................................................................... [1]

e.c

(ii) Write a balanced symbol equation for the reaction.

......................................................................................................................................................................... [1] Which group in the periodic table does lithium belong to?

ctiv

(b) (i)

......................................................................................................................................................................... [1]

ma

(ii) How many electrons are there in its outside shell?

......................................................................................................................................................................... [1]

he

(iii) How many electrons are there in the outside shell of the chlorine? ......................................................................................................................................................................... [1] Use a ‘dot and cross’ diagram to explain how lithium and chlorine react together. Show only the electrons in the outer shell.

ww w.c

(c)

(d)

[3]

Sodium also reacts with chlorine. (i)

Will the reaction be more reactive or less reactive than with lithium?

......................................................................................................................................................................... [1] (ii) What is the common name of the product? ......................................................................................................................................................................... [1]

TOTAL / 10

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 4

The diagram below shows the arrangement of particles in a crystal of sodium chloride. Key + Each particle has a charge. What type of particles have a charge? Choose from: atoms, molecules, ions.

om

(a) (i)

......................................................................................................................................................................... [1]

e.c

(ii) In sodium chloride what is the name of the particle with the positive charge? ......................................................................................................................................................................... [1]

ctiv

(iii) What is the name of the particle with the negative charge?

......................................................................................................................................................................... [1] (iv) What holds the particles together?

The table below gives some information about sodium and chlorine. Complete the table.

symbol

Sodium

Na

Chlorine (c)

electron arrangement

number of electrons in outside shell

number of electron shells

periodic table group number

2.8.1

(i)

(iii)

(v)

ww w.c

element

he

(b)

ma

......................................................................................................................................................................... [1]

(ii)

(iv)

(vi)

C1

2.8.7

[6]

Use the information in the table to explain: (i)

why sodium chloride has positively and negatively charged particles. (Use dot and cross diagrams to help your explanation.)

.............................................................................................................................................................................. ......................................................................................................................................................................... [5] (ii) why the formula for sodium chloride is NaC1. .............................................................................................................................................................................. ......................................................................................................................................................................... [1] TOTAL / 16

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 5

(a) (i)

Explain why there is chlorine in the swimming pool.

om

Sarah is diving into a swimming pool. She can smell chlorine.

......................................................................................................................................................................... [1]

e.c

(ii) Iodine is the same group of the periodic table as chlorine. Give a use of iodine. ......................................................................................................................................................................... [1] Chlorine and iodine are in group 7 of the periodic table. What name is given to group 7 elements?

ctiv

(b) (i)

......................................................................................................................................................................... [1]

ma

(ii) Is chlorine a metal or non-metal?

......................................................................................................................................................................... [1] (iii) Is iodine a metal or non-metal?

The atomic number of chlorine is 17. What does this tell you?

ww w.c

(c) (i)

he

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1] (ii) The electron arrangement of chlorine is 2.8.7. How many electron shells does it have? ......................................................................................................................................................................... [1] (iii) Iodine has five electron shells. How many electrons are in the outer shell of iodine? ......................................................................................................................................................................... [1] (iv) The symbol for chlorine is C1, iodine is I and sodium Na. Chlorine combines with sodium to make sodium chloride, NaC1. Iodine also reacts with sodium. What will be the name and formula of the compound formed? ......................................................................................................................................................................... [2]

TOTAL / 10

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 6

Emma takes a photograph of a friend. Her friend tells her that the film is coated with silver bromide which is sensitive to light. Silver bromide can be made by reacting silver nitrate with sodium bromide. The chemical reaction can be represented as:

What happens to silver bromide in the light?

ctiv

(a) (i)

e.c

om

Ag+(aq) + Br- (aq) ∧ AgBr(s)

......................................................................................................................................................................... [1] (ii) Give another reaction which is affected by light energy.

(b) (i)

What type of particle is Br- ?

ma

......................................................................................................................................................................... [1]

he

......................................................................................................................................................................... [1] (ii) Is silver bromide soluble in water?

(c) (i)

ww w.c

......................................................................................................................................................................... [1] Suggest what would happen if a sample of silver iodide were left in the light.

......................................................................................................................................................................... [1] (ii) Silver iodide can be made in a similar way to silver bromide. Write an ionic equation to show this reaction. Include the state symbols. ......................................................................................................................................................................... [3]

TOTAL / 8

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 7

The symbols represent two different forms of chlorine atoms. 35 17

(a) (i)

C1

37 17

C1

What name is given to atoms of the same element that have different mass numbers?

om

......................................................................................................................................................................... [1] (ii) Why do the atoms have different mass numbers?

......................................................................................................................................................................... [1]

e.c

(iii) What two things does the number 17 tell you about the structure of a chlorine atom? ..............................................................................................................................................................................

ctiv

......................................................................................................................................................................... [2] (iv) Calculate the number of neutrons in an atom of chlorine-35.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (b)

A sample of chlorine is found to have a mass of 35.5. Explain why it is not a whole number.

he

..............................................................................................................................................................................

(c) (i)

ww w.c

......................................................................................................................................................................... [1] A small amount of sodium was burnt in samples of chlorine-35 and chlorine-37. What difference, if any, would you expect between the reactions?

......................................................................................................................................................................... [1] (ii)

Explain your answer.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii)

Would chlorine-35 and chlorine-37 have the same boiling point?

......................................................................................................................................................................... [1] (iv)

Give a reason for your answer.

.............................................................................................................................................................................. ......................................................................................................................................................................... [1] TOTAL / 12

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 8

The table below shows the elements on the third period. Sample of each of the elements were burnt in oxygen and the oxides formed were tested to see whether they were acids or bases.

(a) (i)

12 Mg magnesium 24

13 A1 aluminium 27

14 Si silicon 28

15 P phosphorus 31

How many electron shells does the third period have?

16 S sulphur 32

17 C1 chlorine 35.5

18 Ar argon 40

om

11 Na sodium 23

......................................................................................................................................................................... [1]

e.c

(ii) The element with atomic number 10 is neon. Explain in terms of electron arrangement why a new period starts after neon.

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (b) (i)

Which three elements in the third period are metals?

ma

......................................................................................................................................................................... [1] (ii) What trend do you notice about metallic properties as you go across the period?

(c) (i)

he

......................................................................................................................................................................... [1] Oxygen is in group 6. What does this tell you about the number of electrons in the outside shell?

ww w.c

......................................................................................................................................................................... [1] (ii) Write down formulae for the oxides of sodium, magnesium and aluminium. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3]

TOTAL / 9

GCSE CHEMISTRY

THE PERIODIC TABLE

QUESTIONSHEET 9


Farah has balloons filled with three different gases. The symbols for the gases are written on each balloon. She lets go of the balloons. The diagram shows what happens. He Ne

(a) To which group of the periodic table do the gases belong?

om

Ar

(b) (i)

e.c

......................................................................................................................................................................... [1] Predict what would happen to a balloon filled with krypton.

(ii) Explain the reasons for your answer.

ctiv

......................................................................................................................................................................... [1]

ma

.............................................................................................................................................................................. ..............................................................................................................................................................................

Draw the electron structure of helium.

ww w.c

(c) (i)

he

......................................................................................................................................................................... [2]

[1]

(ii) Explain how the electron structure is related to the chemical properties of helium. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (d) (i)

Helium is often used to fill balloons. Give two reasons why this is a good choice.

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) Neon, argon and krypton are used to fill light bulbs. Give a reason for this. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 11

GCSE CHEMISTRY

THE PERIODIC TABLE

QUESTIONSHEET 10


John has three bottles containing salts. One contains sodium chloride, one lithium chloride and one potassium chloride, but the labels have come off.

B C

Sodium, potassium and lithium all belong to the same group of the periodic table. What is the group number?

e.c

(a) (i)

om

A

ctiv

......................................................................................................................................................................... [1] (ii) What is the name of the group?

......................................................................................................................................................................... [1]

ma

(iii) What colour are the three salts?

......................................................................................................................................................................... [1]

he

John needs to put the correct labels on the bottles. He does a flame test. Describe exactly how he does the flame test. .............................................................................................................................................................................. ..............................................................................................................................................................................

ww w.c

(b)

.............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [3] (c) John puts his results in a table. Look at the table and fill in the names of the salts. Bottle

Colour of flame

A

Yellow

B

Red

C

Lilac

Name of salt

[3]

TOTAL / 9

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 11

The table below gives information about some of the elements in group 7. Symbol

Atomic No.

Melting point (oC)

Boiling point (oC)

Appearance

chlorine

C1

17

-101

-34

greenish gas

bromine

Br

35

-7

58

red liquid

iodine

I

53

114

183

black solid

(a) (i)

om

Element

Put the three elements in the table in their order of reactivity, with the most reactive first.

......................................................................................................................................................................... [1]

e.c

(ii) Which property in the table above indicated the order of reactivity for group 7 elements? ......................................................................................................................................................................... [1] How many electrons are in the outside shell of a chlorine atom?

ctiv

(b) (i)

......................................................................................................................................................................... [1]

ma

(ii) Does the element chlorine usually exist as free atoms, molecules or ions? ......................................................................................................................................................................... [1]

he

(iii) Explain your answer to (ii).

..............................................................................................................................................................................

(c)

ww w.c

......................................................................................................................................................................... [2] Fluorine is also in group 7. Its atomic number is 9. (i)

Draw the electron arrangement for fluorine.

[2]

(ii) Would you expect fluorine to be a solid, liquid or gas at room temperature? ......................................................................................................................................................................... [1] (iii) Predict what its melting point would be. ......................................................................................................................................................................... [1] (d)

A sample of bromine is put in a test tube in a water bath at 60 oC. Suggest what will happen to it. ......................................................................................................................................................................... [1] TOTAL / 11

GCSE CHEMISTRY

THE PERIODIC TABLE

QUESTIONSHEET 12


What colour is the sodium chloride solution?

e.c

(a) (i)

om

Abdul adds some silver nitrate (AgNO3) solution to a sodium chloride (NaC1) solution. He notices a white precipitate. He leaves the test tube in bright sunlight. The precipitate went dark.

......................................................................................................................................................................... [1] (ii) What is meant by ‘precipitate’?

ctiv

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

ma

(iii) What is the name of the precipitate made?

......................................................................................................................................................................... [1] Write a word equation for the reaction.

he

(b) (i)

......................................................................................................................................................................... [1]

ww w.c

(ii) What is the state symbol for a solution in water? ......................................................................................................................................................................... [1] (iii) What is the state symbol for a precipitate? ......................................................................................................................................................................... [1] (iv) Write a symbol equation for the reaction, including the state symbols. ......................................................................................................................................................................... [2] (c)

Abdul adds some silver nitrate to three more solutions, A, B and C. He puts the results in a table. Put a tick in the column if there was a halide present. solution

observation

A B C

no reaction pale yellow precipitate yellow precipitate

observation after leaving in sunlight no change went dark went dark

was a halide present?

[2] TOTAL / 11

GCSE CHEMISTRY

THE PERIODIC TABLE QUESTIONSHEET 13


Below is the first part of the periodic table, giving the elements with their atomic numbers.

0 H 1

Sc 21

Ti 22

V 23

Cr 24

Mn 25

Fe 26

Co 27

Ni 28

Cu 29

Zn 30

III B 5 Al 13 Ga 31

IV C 6 Si 14 Ge 32

V N 7 P 15 As 33

om

(a) (i)

II Be 4 Mg 12 Ca 20

VI O 8 S 16 Se 34

VII F 9 Cl 17 Br 35

He 2 Ne 10 Ar 18 Kr 36

What is the name given to the group between atomic number 21 and 30?

e.c

I Li 3 Na 11 K 19

......................................................................................................................................................................... [1]

ctiv

(ii) Are they metals or non-metals?

......................................................................................................................................................................... [1] (iii) What do the following symbols stand for?

ma

Fe: Zn: Cu: .............................................................................................................................................................................. [3]

(i)

he

Below are some properties of two elements. element A

melting point 1535

boiling point 2750

relative density 7.87

B

97.5

892

0.97

ww w.c

(b)

Which element is from the group between atomic numbers 21 and 30?

......................................................................................................................................................................... [1] (ii) Using the properties in the table, suggest which elements would be most suitable for making a kettle. Give a reason for your answer. .............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(iii) Element number 22 is called titanium. From its position in the periodic table predict three properties you would expect it to have. Put a tick in the box by one property from each pair in the list below. soft can be pulled out to make a wire dull surface that cannot be polished

hard breaks easily when pulled shiny surface that can be polished [3] TOTAL / 11

GCSE CHEMISTRY

THE PERIODIC TABLE

QUESTIONSHEET 14


Copper is a transition element. Name another element from this part of the periodic table.

e.c

(a) (i)

om

Saima heated some copper(II) carbonate (CuCO3) in a test tube. She noticed that the green copper carbonate changed to a black powder. A gas also came off which she passed through a liquid, A.

......................................................................................................................................................................... [1]

ctiv

(ii) What is liquid A?

........................................................................................................................................................................ [1] (iii) Describe what Saima saw happening in A.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [1]

he

(iv) What is the name of the gas?

........................................................................................................................................................................ [1] What is the name of the black powder formed?

ww w.c

(b) (i)

......................................................................................................................................................................... [1] (ii) Saima thinks that a chemical reaction has taken place. Give two pieces of evidence to support her idea. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] (iii) Write a word equation for the reaction. ......................................................................................................................................................................... [1] (iv) Write a balanced symbol equation for the reaction. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY

THE PERIODIC TABLE QUESTIONSHEET 14 CONTINUED

Saima heated two more carbonates, zinc carbonate and sodium carbonate. She put her results in the table below.

(i)

substance

appearance before heating

appearance after heating

gas given off

A

white solid

white solid

no

B

white solid

solid yellow when hot, white when cold

yes

om

(c)

Which substance was zinc carbonate?

e.c

......................................................................................................................................................................... [1] (ii) Explain the reason for your choice.

ctiv

.............................................................................................................................................................................. ..............................................................................................................................................................................

ma

......................................................................................................................................................................... [2] (iii) Explain why no gas was given off with A.

..............................................................................................................................................................................

ww w.c

he

......................................................................................................................................................................... [2]

TOTAL / 14

GCSE CHEMISTRY

THE PERIODIC TABLE

QUESTIONSHEET 15


Three jars containing metal salts have lost their labels. One contains a salt of copper, one a salt of iron(II) and one a salt of iron(III). They can be distinguished by testing with sodium hydroxide solution.

?

?

A

B

C

om

(a) (i)

?

To what part of the periodic table do copper and iron belong?

e.c

......................................................................................................................................................................... [1]

(b) (i)

ctiv

(ii) What is the likely colour of the copper salt? ......................................................................................................................................................................... [1] Describe how to carry out the test with sodium hydroxide, and what would you look for.

..............................................................................................................................................................................

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

(c) (i)

colour of precipitate blue

ww w.c

salt A B C

he

(ii) The table shows the results of testing the three salts with sodium hydroxide. Complete the table. metal ion in salt iron(II)

brown [2]

What is the symbol for the iron(II) ion?

......................................................................................................................................................................... [1] (ii) What is the symbol for the hydroxide ion? ......................................................................................................................................................................... [1] (iii) Write a balanced ionic equation to show the reaction between iron(II) ions and hydroxide ions. ......................................................................................................................................................................... [1]

TOTAL / 9

GCSE CHEMISTRY

THE PERIODIC TABLE

QUESTIONSHEET 16


The table below shows the second and third periods of the periodic table. II

III

IV

V

VI

VII

0

3 Li lithium 7

4 Be beryllium 9

5 B boron 11

6 C carbon 12

7 N nitrogen 14

8 O oxygen 16

9 F fluorine 19

10 Ne neon 20

11 Na sodium 23

12 Mg magnesium 24

13 A1 aluminium 27

14 Si silicon 28

15 P phosphorus 31

16 S sulphur 32

17 C1 chlorine 35.5

18 Ar argon 40

(a) (i)

om

I

The first period is not shown. How many elements are in the first period?

(ii) How many elements are in the second period?

e.c

......................................................................................................................................................................... [1]

ctiv

......................................................................................................................................................................... [1] (iii) What does the period number tell you about the arrangement of electrons in the atom?

(b) (i)

ma

......................................................................................................................................................................... [1] Find carbon in the table. Which period is it in?

(ii) Which group is it in?

he

......................................................................................................................................................................... [1]

ww w.c

......................................................................................................................................................................... [1] (iii) What does the group number tell you about the structure of the carbon atom? ......................................................................................................................................................................... [1] (c) (i)

There are two numbers, 6 and 12, in the box with carbon. 6 is the atomic number. What two things does the atomic number 6 tells you about an atom of carbon?

.............................................................................................................................................................................. ......................................................................................................................................................................... [2] (ii) What is the number 12 called? ......................................................................................................................................................................... [1] (iii) What does the number 12 tell you about the structure of an atom of carbon? .............................................................................................................................................................................. ......................................................................................................................................................................... [1] TOTAL / 10

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 17

Below are the first 36 elements in the periodic table with their atomic numbers.

0 H 1

Sc 21

Ti 22

V 23

Cr 24

Mn 25

Fe 26

Co 27

Ni 28

Cu 29

Zn 30

III B 5 Al 13 Ga 31

IV C 6 Si 14 Ge 32

V N 7 P 15 As 33

VI O 8 S 16 Se 34

VII F 9 Cl 17 Br 35

He 2 Ne 10 Ar 18 Kr 36

Give the symbol for one example of each of the following: (i)

a metal

e.c

(a)

II Be 4 Mg 12 Ca 20

om

I Li 3 Na 11 K 19

......................................................................................................................................................................... [1]

ctiv

(ii) a gas

......................................................................................................................................................................... [1] (iii) a transition element

Find Cl (chlorine) in the table above. (i)

What is the group number?

he

(b)

ma

......................................................................................................................................................................... [1]

......................................................................................................................................................................... [1]

ww w.c

(ii) Which period is it in?

......................................................................................................................................................................... [1] (iii) How many electron shells does it have?

......................................................................................................................................................................... [1] (iv) How many electrons are there in its outside shell? ......................................................................................................................................................................... [1] (c)

Explain what is meant by ‘atomic number’. .............................................................................................................................................................................. ......................................................................................................................................................................... [1]

(Continued...)

GCSE CHEMISTRY

THE PERIODIC TABLE QUESTIONSHEET 17 CONTINUED

(d) (i)

What name is given to the elements in group 0?

......................................................................................................................................................................... [1] (ii) What is the main chemical property of group 0 elements? ......................................................................................................................................................................... [1]

om

(iii) How does their electron arrangement explain this chemical property?

ww w.c

he

ma

ctiv

e.c

......................................................................................................................................................................... [1]

TOTAL / 11

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 18

A

C

B

Identify the elements A, B and C by completing the sentences below. (i)

The element in A was:

e.c

(a)

om

Group one elements react with water and a gas is given off. Lithium, potassium and rubidium were put in separate troughs of water, A, B and C. The diagrams show the reactions. ‘A’ fizzed gently and a gas was given off. ‘B’ reacted violently, burst into flames and cracked the trough. ‘C’ reacted vigorously and burst into flames.

......................................................................................................................................................................... [1]

ctiv

(ii) The element in B was:

......................................................................................................................................................................... [1] (iii) The element in C was:

ma

......................................................................................................................................................................... [1] (b)

The solution left in A was tested with litmus paper. What colour did the litmus paper go?

he

......................................................................................................................................................................... [1] The gas coming off in A was collected in a test tube and tested with a lighted splint. What happened?

ww w.c

(c)

......................................................................................................................................................................... [1] (ii) What is the name of the gas?

......................................................................................................................................................................... [1] (d)

Sodium also reacts with water. (i)

Will the reaction be more or less vigorous than that with lithium?

......................................................................................................................................................................... [1] (ii) What are the names of the products of the reaction? ......................................................................................................................................................................... [1] (e)

Group 1 elements are called ‘alkali metals’. Suggest the reason for this. .............................................................................................................................................................................. .............................................................................................................................................................................. ......................................................................................................................................................................... [2] TOTAL / 10

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 19

(a) (i)

om

Iron and copper are both transition elements. They can both be used to make pans.

Give two physical properties of most transition elements that make them suitable for pans.

..............................................................................................................................................................................

e.c

......................................................................................................................................................................... [2] (ii) Why is copper not often used for pans?

ctiv

......................................................................................................................................................................... [1] (iii) Copper is often used for electric wires. Give two properties of copper that make copper a good choice for this use.

ma

.............................................................................................................................................................................. ......................................................................................................................................................................... [2]

he

(iv) Iron is used to make cars but not aeroplanes.

Give one property of iron that makes it good to use for cars.

ww w.c

......................................................................................................................................................................... [1] Give one property of iron that makes it unsuitable for planes. ......................................................................................................................................................................... [1] (b) (i)

Iron is used as a catalyst in the Haber process to make ammonia. What is the purpose of a catalyst?

......................................................................................................................................................................... [1] (ii) Platinum is used as a catalyst in catalytic converters in cars. Where in the periodic table would you expect to find platinum? ......................................................................................................................................................................... [1] (c) (i)

Copper and iron both form ions with non-metals. What type of ions do they form?

......................................................................................................................................................................... [1] (ii) Write the symbols for a copper(II) ion and an iron(III) ion. ......................................................................................................................................................................... [2] TOTAL / 12

GCSE CHEMISTRY

THE PERIODIC TABLE


QUESTIONSHEET 20

The following diagram shows part of the periodic table in which letters represent some elements. (These are not chemical symbols)

B

F

om

A

G

C D

E

Give the letter that represents the element that

is an unreactive gas .................................................................................................................... [1]

II

has one electron in its outside shell ........................................................................................... [1]

III

is in the same group as F ............................................................................................................ [1]

IV

is a yellow/green gas .................................................................................................................. [1]

V

is in the same period as E ........................................................................................................... [1]

VI

forms several coloured compounds ............................................................................................ [1]

VII

is used in light bulbs .................................................................................................................. [1]

he

ma

ctiv

I

ww w.c

(i)

e.c

You may use each letter once, more than once or not at all in this question.

TOTAL / 7

GCSE CHEMISTRY

ACIDS, BASES & SALTS ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 change pH to 7

1

(ii)

burette/measuring cylinder/syringe

1

(i)

1g

1

(ii)

30/10 =3g

1 1

(iii)

concentration of sodium hydroxide

1

(c)

om

(b)

(i)

6 g in 100g ⇒ no

e.c

(a)

1. 2. 3. 4.

magnesium zinc nickel copper

ma

(a)

ctiv

QUESTIONSHEET 2

1 1 TOTAL 8

2

(c)

(i)

hydrogen

(ii)

burning splint/ignite/burn the gas squeaky pop

2

(i)

magnesium chloride

1

(ii)

ionic

1

(iii)

the forces of attraction/bonding between the ions are very strong large amount of energy required to break them

ww w.c

(b)

he

4 correct answers score 2 marks 2 correct answers score 1 mark

1

2

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 3 sodium + oxygen → sodium oxide

1

(ii)

Na2O

1

(iii)

solid

1

(iv)

purple

1

(i)

O2 (g) 2

(ii)

accept answer between 4 and 6

(iii)

any two from corrodes buildings/statues/metalwork kills/damages trees causes lakes to become acidic/kills animal and plant life

ctiv

e.c

(b)

(i)

om

(a)

QUESTIONSHEET 4 covalent

(ii)

N

H

1

8 electrons around N scores 1 mark correct bonding pairs scores 1 mark

2

forces between the molecules/ particles are weak these forces are easily overcome

2

particles move/ have kinetic energy randomly/in all directions or diffusion takes place from high concentration to low concentration

2

(ii)

molecules/particles of ammonia are lighter

1

(iii)

ammonium chloride

1

(iii)

(b)

H

ww w.c

H

TOTAL 9

ma

(i)

2

he

(a)

1

(i)

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 5

(c)

carbon dioxide limewater turns milky/white/cloudy

1 1

(ii)

calcium sulphate

1

(i)

increases

1

(ii)

greater surface area particles collide more often

1 1

(i)

hydrogen

(ii)

burning splint/produces squeaky pop

(iii)

manufacture of ammonia/manufacture of margarine

ma

bromophenol blue

(ii)

bromophenol blue and thymol blue

he

(i)

ww w.c

(b)

One mark each for: yellow colourless yellow blue

1 2 1 TOTAL 10

ctiv

QUESTIONSHEET 6 (a)

om

(b)

(i)

e.c

(a)

4 1 2 TOTAL 7

QUESTIONSHEET 7 (a)

calcium hydroxide

1

(b)

8 5 10 5 125 = 10 000 g/10 kg

1 1

(c)

calcium oxide is corrosive/harms skin

1

(i)

Ca(OH)2 + 2HNO3 Æ Ca(NO3) 2 + 2H2O

2

(ii)

1 mol Ca(OH)2 neutralises 2 mol HNO3 74 g Ca(OH)2 neutralises 126 g HNO3 37 g Ca(OH)2 is needed to neutralise 63 g HNO3

1 1 1

(d)

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 8 (a)

SO2 + Cl2 + 2H2O Æ H2SO4 + 2HCl (correct formulae 1, balancing 1)

2

(b)

71g Cl2 react with 64 g SO2 so 71 mg Cl2 react with 64 mg SO2 64 = 0.9 mg SO2 and 1 mg Cl2 reacts with 71

1 1

A 10 / 2 = 5 B is greater

1 1

om

B 50 / 5 = 10

e.c

(c)

1

12

(ii)

lemon juice

(iii)

7 red or orange

(b)

1 1 1 1

(i)

accept any pH greater than 7 up to 14

1

(ii)

neutralisation

1

(iii)

water

he

(c)

ma

(i)

ww w.c

(a)

ctiv

QUESTIONSHEET 9

TOTAL 7

1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 10 1

(b)

(i)

neutralisation

1

(ii)

reaction is faster/increases rate of the reaction increases surface area/more collisions between particles

2

2 CO2

2

(i)

(ii)

turns milky/white/cloudy

(iii)

24 + 12 + (16 5 3) = 84

ctiv

e.c

(c)

om

green

(a)

QUESTIONSHEET 11

(c)

TOTAL 9

(ii)

neutralisation

(iii)

7

(i)

hydrogen ion/H

(ii)

hydroxide ion/OH-

(iii)

H+ + OH- → H2O

1

(i)

it is corrosive

1

(ii)

any two from safety goggles plastic gloves wear lab coat use a tray to catch spillage

2

ma

burette

+

he

(b)

1 1

(i)

ww w.c

(a)

1

1 1 1 1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 12 1

(ii)

hydrogen

1

(i)

blue/purple

1

(ii)

hydroxide ion

1

(i)

7

1

(ii)

sodium sulphate

(iii)

2NaOH 2H2O

(d)

om

(c)

red

e.c

(b)

(i)

a fertiliser

ctiv

(a)

remains of dead plants became buried action of heat and pressure in the absence of oxygen over millions of years any three marks

he

(a)

2 1 TOTAL 9

ma

QUESTIONSHEET 13

1

3

gain of oxygen/loss of hydrogen/loss of electrons

1

(ii)

sulphur dioxide

1

(c)

H2O + SO2 ∏ H2SO3

2

(d)

limestone is a carbonate acids react with carbonates

1 1

ww w.c

(i)

(b)

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 14 A

1

(b)

B

1

(c)

C

1

(d)

F

1

(e)

D

1

(f)

B

(g)

A

e.c

om

(a)

MgCO3 calcium carbonate fizzes

(b)

MgCl2

TOTAL 7

1 2 1

add acid slowly/ from a burette until indicator changes colour

1 1

(ii)

as a control/ for a fair test

1

(i)

0.7 5 16 = 1.2 5 11 = 0.6 5 7.5 = 0.4 5 22 =

(ii)

magnesium hydroxide cheapest no gas given off

11.2 p 13.2 p 4.5 p 8.8 p

he

(d)

1

(i)

ww w.c

(c)

ma

(a)

ctiv

QUESTIONSHEET 15

1

1 1 1 1 1 1 1 TOTAL 14

GCSE CHEMISTRY


QUESTIONSHEET 16

(b)

(i)

does not react with acid

1

(ii)

substance A very high pH – dangerous

1 1

(iii)

a carbonate

1

(i)

seasoning preserving foods

1 1

(ii)

two from: sodium carbonate, chlorine, sodium, sodium hydrogencarbonate

om

(a)

e.c

(iii ) to melt ice

vinegar is acid ammonia is alkaline they neutralise the stings

(c)

water dilutes acid washing soda neutralises it

ma

(b)

he

add universal indicator/litmus red ⇒ acid

ww w.c

(a)

ctiv

QUESTIONSHEET 17

2 1 TOTAL 9

1 1 1 1 1 1 1 TOTAL 7

QUESTIONSHEET 18 (a)

field C

(b)

A beans, onion, leek

3

B beans, leek

2

(c)

1

C potato

1

field C

1 TOTAL 8

GCSE CHEMISTRY



MgSO4

1

(b)

I magnesium & sulphuric acid II magnesium carbonate & sulphuric acid III magnesium hydroxide & sulphuric acid

2 2 2

(c)

boil off/evaporate the water

1

om

TOTAL 8

he

ma

ctiv

seven/7 neutral/ neutralised hydrogen/ hydrogen ions carbon dioxide ethanoic acid lemons/car batteries/nettles etc sodium hydroxide/potassium hydroxide/ammonia etc corrosive

ww w.c

(i) (ii) (iii) (iv) (v) (vi) (vii) (viii)

e.c

QUESTIONSHEET 20

1 1 1 1 1 1 1 1 TOTAL 8

GCSE CHEMISTRY

ATOMIC STRUCTURE & BONDING ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 (a)

(b)

oxygen 2 6 (0) sulphur 2 8 6

1 1

(i) 8P 8N

(i)

chlorine radicals have unpaired electrons are chlorine atoms OR chlorine molecules have no unpaired electrons are pairs of chlorine atoms

1 1

CFCs/chlorofluorocarbons (NOT – aerosols, fridges etc as these are not substances)

1

ctiv

e.c

lose 6 electrons gain 2 electrons

(ii)

he

QUESTIONSHEET 2

1 1

1 1

TOTAL 9

(i)

outer shell electron furthest from nucleus

(ii)

all electrons in same shell

1

(iii)

nearest electrons to nucleus

1

ww w.c

(a)

1 1

(ii)

ma

(c)

om

correct nucleus correct electronic arrangement

(b)

energy

1

2 3 number of electrons

4

three electrons in outside shell after this removing from next shell in

1 1

1

1 1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 3 (a)

(i)

relative atomic mass/mass number = 40 atomic number/proton number = 20

1 1

(ii)

protons – 20 neutrons – 20 electrons – 20

1 1 1

(b) electrons 0 2 23 54 36

om

neutrons 0 5 30 74 45

(a)

he

10P 12N

TOTAL 13

ww w.c

(b)

½ mark each rounded to whole number

ma

QUESTIONSHEET 4

10P 10N

8

ctiv

e.c

protons 1 4 26 53 34

correct and same electronic arrangement correct and same protons in each correct neutrons

1 1 1

90/100 × 20 = 18 10/100 × 22 = 2.2 relative atomic mass = 18 + 2.2 = 20.2 (correct answer alone scores 3)

1 1 1

Note: that the answer alone scores full marks. Always show working as an incorrect answer with no working will score zero. Correct working will gain some marks. (c)

all chemical properties are the same chemical properties depend on number of electrons electrons are the same in both isotopes

1 1 1

TOTAL

9

GCSE CHEMISTRY


QUESTIONSHEET 5

(d)

1

(ii)

argon

1

(i)

20

1

(ii)

Calcium ion/Ca2+

1

(i)

1/ one

1

(ii)

20

1

(i)

7/ seven

(ii)

37

om

(c)

18

1 1

e.c

(b)

(i)

TOTAL 8

ctiv

(a)

QUESTIONSHEET 6 13 protons 11 neutrons 13 electrons

1 1

(b)

atoms with same number of protons/ atoms of same element with different numbers of neutrons

1 1

(c)

both isotopes have same number of electrons/ arrangement of electrons it is number/arrangement of electrons that determines chemical behaviour

1 1

(d)

25/100 × 24 = 6 75/100 × 28 = 21 6 + 21 = 27 (correct answer alone scores 3)

1 1 1

ww w.c

he

ma

(a)

Note: that the answer alone scores full marks. Always show working as an incorrect answer with no working will score zero. Correct working will gain some marks. (e)

aluminium/Al

1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 7 (a) (b) (c) (d) (e) (f) (g)

B E A F A B & C/C & B D & E/E & D/D & F/F & D

1 1 1 1 1 1 1

om

TOTAL 7

QUESTIONSHEET 8

(ii)

2,8,7

(i)

atoms become stable by obtaining full outer shells calcium loses 2 electrons chlorine gains one electron electrons transferred from calcium atoms to chlorine atoms

1 1 1 1

(ii)

Ca2+, Cl−

2

(iii)

CaCl2

ionic bonds/forces between ions/particles are very strong they take a lot of energy to break/overcome

ww w.c

he

(c)

e.c

2,8,8,2

ctiv

(b)

(i)

ma

(a)

1 1

1 1 1

TOTAL 11

QUESTIONSHEET 9 (a) (b)

(c)

covalent

1

(i)

bonds between atoms are very strong require a lot of energy to break

1 1

(ii)

atoms arranged in layers forces between layers weak/layers slide past each other easily

1 1

free electrons move along the layers

1 1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 10 regular pattern of ions tightly packed free electrons hold structure together (All four marks could be obtained from a clearly labelled diagram)

+

+

+ -

+ -

+ -

+ -

-

-

-

+ +

+

-

+ -

1 1 1 1

-

+ -

+ -

om

Positively charged metal ions

e.c

(a)

Electrons

forces holding lattice together are strong ions/atoms in lattice tightly packed

(ii)

layers of ions/atoms can slide past each other

1

(c)

free electrons take in heat passed on as electrons collide

1 1

(d)

alloy

(a)

(b)

(i)

2,8,1

(ii)

2,8,7

(i)

Na+

(ii)

Cl−

(c) (d)

(e)

NaCl

ma

ww w.c

QUESTIONSHEET 11

ctiv

(i)

he

(b)

1 1

1

TOTAL 10

1 1 1 1 1

(i)

ions able to move freely

1

(ii)

melt it

1

(i)

inert/noble gas/ Group 0

1

(ii)

has a full outer shell

1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 12

(ii)

one potassium with 1+ needed to cancel 1- in nitrate KNO3

1 1

(iii)

one calcium 2+ needed to cancel 1- in two chlorines CaC12

1 1

(iv)

one magnesium 2+ needed for two nitrates 1Mg(NO3) 2

1 1

(v)

one potassium 1+ needed for one chloride 1KC1

(i)

ionic

(ii)

electrons are transferred from one atom to another

(i)

I-

(ii)

Sr2+

(iii)

SrI2

ctiv

e.c

om

1 1

ma

(c)

two sodium with 1+ needed to cancel 2- in sulphate Na2SO4

he

(b)

(i)

ww w.c

(a)

1 1 1 1 1 1 1 1

TOTAL 16

GCSE CHEMISTRY


QUESTIONSHEET 13

(b)

(i)

simple molecular

1

(ii)

giant atomic

1

(iii)

simple molecular

1

(iv)

giant metallic

1

(v)

giant ionic

1

both will be low

1

om

(a)

Co2+

Co2+

Co2+

Co2+

Co2+

Co2+

Co2+

Co2+

Co2+

Co2+

Sea of electrons

ctiv

Co2+

e.c

(c)

ma

Co2+

1 1

TOTAL 8

ww w.c

he

regular arrangement of cobalt ions surrounded by free electrons

QUESTIONSHEET 14 (a) (b) (c) (d) (e) (f) (g)

A & E/E & A B B & D/D & B C F E F

2 1 2 1 1 1 1

Note: that you may use each atom once, more than once or not at all. This is sometimes stated on the question paper. Students often go wrong by thinking that they must use all the alternatives at some point in the answer.

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 15 4

1

(ii)

4

1

1

1

(i)

4

1

(ii)

2

1

(i)

carbon & silicon/silicon & carbon/C & Si/Si & C

(ii)

four electrons in outer shell of both means they are both in group 4

(b) (c)

(d)

(iii)

positive/+/+12

(c) (i)

(ii)

2,8,2

1 1 1

TOTAL 8

1 1 1 1 1 1

two/2/II has two electrons in outer shell

1 1

three/3/III outer electrons in third shell/energy level

1 1

ww w.c

(ii)

12

he

protons neutrons

ma

nucleus

(ii)

(b) (i)

ctiv

QUESTIONSHEET 16 (a) (i)

om

(i)

e.c

(a)

TOTAL 10

GCSE CHEMISTRY



K2O

1

(ii)

MgO

1

(iii)

Al2O3

1

(i)

FeO Fe2O3

1 1

(ii)

iron(II) oxide & iron(III) oxide

1

e.c

om

(b)

(i)

QUESTIONSHEET 18

sodium sulphate

(iii)

sodium hydrogencarbonate

(i)

sodium sulphate/ Na2SO4

(ii)

7

(i)

sodium hydrogencarbonate/ NaHCO3

(ii)

sodium (no marks as given in question) hydrogen carbon oxygen

ctiv

(ii)

ma

(c)

sodium chloride

he

(b)

(i)

ww w.c

(a)

TOTAL 6

1 1 1 1 1 1

1 1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 19

e.c

om

One mark each for the following in the correct order smallest neutrons positive negative nucleus equal ion atomic number mass number/atomic mass different protons electrons neutrons

ctiv

QUESTIONSHEET 20

sodium Na 23 11 12

he

magnesium Mg 24 12 12

ww w.c

neon Ne 20 10 10

ma

one mark each Name of element symbol mass number atomic number number of neutrons

TOTAL 13

nitrogen N 14 7 7

carbon C 12 6 6

TOTAL 9

GCSE CHEMISTRY

ENERGETICS ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1

(i)

random arrangement of molecules, quite close together able to move freely in body of liquid

1 1

(ii)

widely spaced random arrangement able to move freely in whole container

1 1

evaporation

1

(i) H

(ii) (e)

H

H

H

H

C

C

C

C

H

H

H

H

2

separate molecules with low attraction

1

energy needed to start reaction called activation energy

1 1

QUESTIONSHEET 2

TOTAL 12

(i)

to allow gases to pass through

(ii)

as a conductor

1

(b)

produce electricity directly from fuel

1

(c)

2H2 + O2 Æ 2H2O (one for formulae, one for balancing)

2

(d)

do not run down as quickly produce water for use by astronauts

1 1

(e)

solar cell

1

ww w.c

(a)

H

e.c

(d)

ctiv

(c)

om

1 1

ma

(b)

butane is easier to light charcoal is less expensive/is easier to store

he

(a)

1

TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 3

(b)

(i)

burns quicker/more completely

1

(ii)

heat transferred to water more efficiently

1

(i)

6H2O + 6CO2

1 1

(ii)

31 200 × 100/2 = 1 560 000 J or 1560 kJ

1 1

om

(a)

(a)

(i)

e.c

QUESTIONSHEET 4 solution

ctiv

energy

ma

crystals time

1 1 1

(ii)

breaking bonds in ammonium nitrate takes in energy making bonds between ions and water molecules gives out energy former exceeds the latter

1 1 1

(i)

2Al + Fe2O3 Æ Al2O3 + 2Fe

2

(ii)

match supplies activation energy the reaction supplies it after that

1 1

ww w.c

(b)

he

energy taken in from surroundings

TOTAL 6

TOTAL 10

QUESTIONSHEET 5 (a)

treacle pudding contains carbohydrate for energy sumo wrestler needs protein for muscle

1 1

(b)

sugar is a simple carbohydrate may cause obesity

1 1

TOTAL 4

GCSE CHEMISTRY


QUESTIONSHEET 6 (a)

Bond breaking = 436 + 151 = 587 Bond making = 2 × 298 = 596 Difference = -9 kJ

1 1 1

(b)

Exothermic

1

(c)

H2 +I2

om

energy

e.c

2HI

Heat energy = 4.2 × 15 × 20 = 1260 J = 1.26 kJ

(b)

Moles =

10 × 0.1 = 0.001 1000

= 1 ×10-3

ma

(a)

ctiv

QUESTIONSHEET 7

HCl(aq) + NaOH(aq) Æ NaCl(aq) + H2O(l)

(d)

1000 × (a) = 1260 kJ

ww w.c

he

(c)

3

TOTAL 7

1 1 1 1 1 1 1 TOTAL 7

QUESTIONSHEET 8 (a)

(i)

Br-Br + H-H/193 + 436 = 629

1 1

(ii)

2 × H-Br/2 × 366 = 732

1 1

(iii)

overall energy change = energy in – energy out/ 629 – 732 = -103 (+ 103 scores 1 mark.)

1 1

(b)

exothermic/ energy given out/ energy supplied to surroundings (give follow through mark)

1

(c)

b

1 TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 9 to find out how much fuel was used

1

(ii)

to ensure an even temperature

1

(iii)

the temperature of the water

1

(iv)

the volume of water distance of burner from beaker

1 1

(i)

12oC/g

1

(ii)

propanol propanol is bigger molecule contains more carbon

om

(b)

(i)

e.c

(a)

(b)

TOTAL 9

bubbling/ fizzing/ slight movement of calcium clouding of water

1 1

(i)

energy produced = 4.2 × 5 × 50 =1050 J (or 1.050 kJ)

1 1

(ii)

Exothermic

ma

(a)

ctiv

QUESTIONSHEET 10

1 1 1

Ca(s) + 2H2O(1) ™ Ca(OH)2(aq) + H2(g) Ignore state symbols

ww w.c

he

(c)

1 2

TOTAL 7


(b)

(i)

open

(ii)

more oxygen mixes with the methane

1

(i)

hydrogen carbon

2

carbon dioxide water

2

the minimum energy for a reaction to happen

2

lowers the activation energy

1

(ii)

(c)

(i)

(ii)

1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 12 exothermic heat is given out/ temperature rises

2

(ii)

17oC

1

(iii)

paraffin

1

(iv)

to make the test fair/ so the results are comparable

1

(b)

oxygen

1

(c)

causes global warming/ greenhouse effect polar ice caps melt causing flooding carbon monoxide

ctiv

e.c

(d)

(i)

om

(a)

QUESTIONSHEET 13

2 1 TOTAL 9

ethanol smallest temperature rises

(b)

to make the test fair different amounts of water require different amounts of heat to raise temperature by 1oC

1 1

(c)

100 × 4.2 × 39 = 16380 J for 1.0 g for 2.0 g: 16380 × 2 = 32760 J (=32.76 kJ)

1 1 1

ww w.c

he

ma

(a)

1 1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 14

energy

reactants

activation energy

(a)

reactants and products labelled

(b)

activation energy labelled

(ii)

32 g O2 reacts with 48 g Mg 8 g O2 reacts with 12 g Mg 8 g O2 occupies 6 dm3

1 1 1

ctiv

e.c

1 1 1

TOTAL 8

exothermic

(ii)

they are being used up faster than they can be replaced so they will eventually run out

2

wood/ paper/ peat/ biogas/ charcoal any two

2

C-H O=O

2

(ii)

(iii)

C=O H-O

ww w.c

(i)

he

(i)

(iii)

(b)

1

formula mass of MgO = 24 + 16 = 40 40 g MgO produced from 24 g Mg 100 g MgO produced from (24 × 100)/ 40 = 60 g Mg


1

(i)

ma

(c)

om

products

bonds broken =4 C-H + 2 O=O energy in = (4 × 435) = (2 × 497) energy change = 2734 – 3462 energy change = -728 kJ

1

2 bonds formed = C=O + 4 H-O energy out = (2 × 803) + (4 × 464)

1 1 1 1

correct answers score 4 marks TOTAL 13

GCSE CHEMISTRY


QUESTIONSHEET 16 (a) (b)

(i)

(ii)

the reading would increase

1

substance which speeds up/ increases the rate of a chemical reaction is chemically unchanged/ remains the same

2

reading goes up to the same point as before reading goes up quicker

2

om

TOTAL 5

thermometer

(ii)

57 – 19 = 38

(iii)

any temperature at least 5 degrees above 38

(b)

exothermic (i)

any combustion, any displacement etc

(ii)

can be used to supply energy

(iii)

can be used to cool injuries etc.

(a)

1 1 1 1 1 1 1

TOTAL 7

Two from state of health, age, type of job

2

325 + 1430 + 660 + 200 = 2615 J

1 1

(i)

man would be fatter farmer more muscular

1 1

(ii)

he does not take in enough energy

1

(iii)

eat less take exercise

1 1

(b)

(c)

ww w.c

QUESTIONSHEET 18

ma

(c)

ctiv

(i)

he

(a)

e.c

QUESTIONSHEET 17

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 19

(c)

(d)

2

less coal for amount of air/oxygen mixes better to burn more easily

2

oxygen needed for combustion air only contains 20% oxygen

2

carbon dioxide carbon monoxide

om

(b)

larger surface area of coal oxygen/air can mix with it more easily

QUESTIONSHEET 20

(c)

(i)

heat same mass of water with each fuel measure temperature rise weigh burners before and after experiment to calculate amount of fuel used

1 1 1 1

(ii)

coal does not light and continue to burn as easily

1

(iii)

difficult to measure amount of gas used

1

we don’t know how much fuel was used

1

ma

ctiv

3

he

(b)

TOTAL 8

Three from lights easily, easy to store, safe to store, continues to burn, no pollution

ww w.c

(a)

2

e.c

(a)

TOTAL 10

GCSE CHEMISTRY

INDUSTRIAL PROCESSES ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 proteins /amino acids

1

(b)

nitrate will be used up eventually / will run out

1

(i)

23 + 14 + (3 × 16) = 85

1

(ii)

14 / 85 × 100 = 16.5 (16.47) if incorrect, one mark is given for the correct fraction (ii) is marked consequentially on part (i)

2

(i)

air

(ii)

water / natural gas / methane

(i)

iron acts as a catalyst

(ii)

this increases surface area and increases the rate of reaction

(e)

e.c

(d)

ctiv

(c)

om

(a)

sulphuric acid

(g)

increase in plant/algal growth plants/algae die and rot the rotting process uses up oxygen in the water lack of oxygen results in death of fish and other wildlife

ww w.c

he

ma

(f)

1 1 1 1 1 1 1 1 1 1

TOTAL 15

GCSE CHEMISTRY

INDUSTRIAL PROCESS ANSWERS AND MARK SCHEMES

QUESTIONSHEET 2 provides raw materials to make useful products provides jobs for people adds valuable income to the local community

1 1 1

(b)

THREE from : -removes a mineral that cannot be replaced -damages habitats of plants and/or animals -spoilheaps produced that are unsightly -named form of pollution from mining eg.noise/more lorries/dust

3

(ii)

CaCO3 : 100 CaO : 56 CO2 : 44

(i)

100 tonnes limestone Æ 56 tonnes calcium oxide 300 tonnes Æ 168 tonnes 3,000 tonnes Æ 1680 tonnes marked consequentially on the masses given in (c)

(e)

ctiv

some limestone remains unreacted/does not get hot enough

ma

(ii)

e.c

(s) = solid (g) = gas

glass making / cement making / building material / neutralising agent for soils

he

(d)

(i)

ww w.c

(c)

om

(a)

1 1 1 1 1

2

1 1 TOTAL 15

GCSE CHEMISTRY


QUESTIONSHEET 3 anode correctly labelled – electrode on left

1

(b)

Test – use damp litmus paper Result - turns white / bleached

1 1

(c)

kill bacteria in drinking water or swimming pools / manufacture of PVC or bleach or disinfectants

1

(d)

2Cl - → Cl2 + 2e-

1

(e)

hydrogen

1

(i)

solution is alkaline

(ii)

sodium hydroxide

e.c

(f)

om

(a)

1 1

FIVE from : - run cell with known concentration of salt solution - measure volume of gas collected after specified time/ time how long to collect a specified volume of gas - repeat experiment with weaker/stronger concentration of salt solution - use same volume of solution - use same electrodes - use same current 5

(h)

increase current of cell use different electrodes

ww w.c

he

ma

ctiv

(g)

1 1

TOTAL 15

GCSE CHEMISTRY


QUESTIONSHEET 4 (a)

Al3+ O2-

1 1

(b)

lowers melting point of the aluminium oxide

1

(c)

ions need to be free to move towards the electrodes ions are able to move as a liquid / ions unable to move as a solid

1 1

Al3+ + 3e- Æ

1

(ii)

1 1 1 1 1

(i)

United Kingdom

1

(ii)

TWO from: - large amount of electricity not available - money for construction of plant not available - lack of suitable trained workforce

ctiv

e.c

method of extraction from the ores is related to a metal's position in the reactivity series metals at the top of the series need more energy than those lower down

ma

(f)

oxide ions are attracted to the anode oxide ions lose electrons to form oxygen gas

he

(e)

Al

om

(i)

ww w.c

(d)

2 TOTAL 14

GCSE CHEMISTRY


QUESTIONSHEET 5 Æ CO2

(a)

C + O2

(b)

sulphur dioxide reacts with oxygen in the air and dissolves in water forming sulphuric acid or 'acid rain' making the soil too acidic and damages the roots of the trees/ rain water is very acidic and attacks or damages leaves

1 1

(i)

neutralisation

1

(ii)

CaO : 56 SO2 : 64

1 1

(iii)

32 / 64 × 56 = 28 tonnes if incorrect, 1 mark is given for the fraction mark consequentially on answers to (ii)

(iv)

TWO from : -do not want sulphur dioxide to escape so best to have excess calcium oxide -would be difficult to ensure thorough mixing of reactants -impurities may be present in calcium oxide / may be impure

2

(i)

reaction is reversible/products break up to reform reactants

1

(ii)

sulphur trioxide

1

(iii)

sulphuric acid

om

1

2

e.c

ctiv

ma he

(d)

ww w.c

(c)

1

1

TOTAL 14

GCSE CHEMISTRY


QUESTIONSHEET 6

(ii)

line drawn from the reactants to the top of the curve

1

(iii)

speeds up the reaction / makes the reaction go faster

1

(i)

70 %

1

(ii)

70 / 100 × 300 = 210 tonnes if incorrect one mark is awarded for the correct fraction mark consequentially on the answer to (c) (i)

(iii)

low rate of reaction / slow reaction low temperature makes the catalyst less effective

om

1

2

1

(i)

SO3 + H2SO4 Æ H2S2O7 one mark for correct reactants, one mark for correct products

2

(ii)

the reaction is too violent / too exothermic

1

(i)

transition metal / transition element

1

(ii)

vanadium catalyst is not used up in the reaction

ctiv

(e)

the minimum amount of energy needed to start a reaction

ma

(d)

(i)

he

(c)

1

ww w.c

(b)

+ 189 kJ

e.c

(a)

1

TOTAL 13

GCSE CHEMISTRY


QUESTIONSHEET 7 amount or percentage of copper present is very small

1

(b)

reacts in air to form sulphuric acid this is the cause of 'acid rain' poisonous / causes pollution scores one mark

1 1

(c)

sulphur dioxide reacted with air or oxygen to form sulphur trioxide sulphur trioxide absorbed into concentrated sulphuric acid

1 1 1

copper from the anode/impure electrode forms copper ions or dissolves copper ions turn to copper on cathode/deposited on cathode/pure copper impurities are left behind/fall to the bottom of the cell

1 1 1

(ii)

2e-

1

(iii)

‘reduction’ is electron gain copper ions gain two electrons

(iv)

'anode slime' contains precious metals/named metals eg. silver, gold

1

high melting points form coloured compounds

1 1

QUESTIONSHEET 8

ctiv

1 1

TOTAL 15

(i)

1.03%

(ii)

oxygen

(b)

(i) (ii) (iii)

fractional distillation argon oxygen

(c)

carbon dioxide & water vapour

2

(d)

(i) (ii)

1 1

(e)

convert iron to steel (1) by burning impurities (1)

ww w.c

(a)

ma

(e)

e.c

(i)

he

(d)

om

(a)

in electric bulbs, for risky welding jobs, etc. fast freezing food, for packing food, making ammonia, etc.

1 1 1 1 1

2

TOTAL 11

GCSE CHEMISTRY

INDUSTRIAL PROCESS ANSWERS AND MARK SCHEMES QUESTIONSHEET 9 1

(i)

NO

1

(ii)

O2

1

(iii)

NO2

1

(c)

platinum

1

(d)

gases are cooled using water

(e)

reacted with water and oxygen

1 1 1

ammonia solution / ammonium hydroxide

(ii)

neutralisation

(iii)

nitrogen is converted into plant protein crop yield is therefore increased

1 1

(iv)

10% nitrogen 5% potassium no phosphorus is present

1 1 1

ma

ctiv

(i)

he

(f)

ww w.c

(b)

om

air

e.c

(a)

1 1

TOTAL 15

GCSE CHEMISTRY


QUESTIONSHEET 10 iron

1

(b)

3H2 2NH3

1 1

(c)

a reaction in which the products reform the reactants

1

(i)

increases as the pressure increases decreases as the temperature increases

1 1

(ii)

temperature 300oC

(iii)

line drawn between 300oC and 500oC lines and is closer to 300oC line

1

Two from: - more expensive plant or pipelines as they need to be thicker/stronger - greater risk of explosion / greater danger to workforce - higher power costs for compressor

2

e.c

(e)

pressure 225 atmospheres

ctiv

(d)

om

(a)

1

lower rate of reaction / reaction takes a long time

1

(g)

cool down the mixture of gases ammonia will be the first to turn into a liquid

1 1

(h)

recycled

ww w.c

he

ma

(f)

1

TOTAL 14

GCSE CHEMISTRY


QUESTIONSHEET 11

(b)

(c)

haematite/magnetite

1

(i)

carbon reacts with oxygen to form carbon dioxide this reacts with more carbon

1 1

(ii)

oxygen is removed

1

(i)

CaCO3

(ii)

limestone removes acid/sandy impurities

Æ

CaO + CO2

2 1

om

(a)

molten iron slag

(e)

need for shift work / unsociable hours

(f)

THREE from : -near to supply of coal/coke or near to coalfield -near to a port for import of ore -good communication links eg. good road or rail links -availability of skilled workforce

3

steel girders for construction / motor car bodies / shipbuilding

1 1

ctiv

ma

he ww w.c

(g)

e.c

(d)

1 1 1

TOTAL 15

GCSE CHEMISTRY



2

THREE from : - high demand reduces the Earth's resources - more fuel burnt that adds to atmospheric pollution/greenhouse effect/increase in carbon dioxide levels - bauxite ore will run out/is a non-renewable resource - problems involved in more recycling to meet the increased demand - more waste produced from purification of bauxite - more land used to build HEP plants to meet electricity demand

3

(ii)

oxygen formed at the anode reacts with the carbon forming carbon dioxide gas

(i)

Al3+

(ii)

molar mass of oxygen = 32 g each O2 releases 4 electrons to form 4/3 aluminium 4/3 × 27 × 10 = 360 tonnes

3e- Æ

Al

ma

+

ctiv

anode connected to +; cathode to − electrolyte – the solution aluminium metal – the bottom layer

he

(d)

(i)

ww w.c

(c)

e.c

om

(b)

TWO from : - large amount of impurities present in ore/ only one tonne of metal formed from every 4 tonnes of ore - large amounts of energy required in the extraction process/ uses large amounts of electricity - special equipment required to cope with the high temperatures involved

1 1 1 1 1 1 1 1 1

TOTAL 14

GCSE CHEMISTRY


QUESTIONSHEET 13 (i)

oxygen

1

(ii)

vanadium(V) oxide

1

(iii)

water

1

(iv)

(s)

(v)

toxic nature of the gas/forms acid rain

(vi)

hydrogen, sulphur and oxygen

O2 (g)

2

om

1

(vii) dangerous reaction/ a sulphuric acid mist is formed

ctiv

e.c

(viii) paints/fertilisers/car batteries/detergents/plastics/cleaning metals/ many more

QUESTIONSHEET 14

(c)

TOTAL 9

iron behaves as a catalyst in speeding up the reaction

1

(iii)

heat speeds up the reaction

l

(i)

as the pressure increases % of ammonia also increases as the temperature increases % of ammonia decreases construction cost or plant too dangerous

1 1 1

ma

(ii)

(ii)

2 (l)

1

N2 (1)

sulphuric acid

he

(b)

3

1

(i)

ww w.c

(a)

1

2

1

TOTAL 8


(b)

(i)

(I) coke (II) limestone

1 1

(ii)

slag

1

(i)

carbon monoxide

1

(ii)

2×56 + 3 ×16 =160

1 1

(iii)

1 mole of Fe2O3 gives 2 moles of Fe 320 tonnes gives 224 tonnes of iron

1 1 TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 16

(ii)

breaking down a substance by electricity

1

(iii)

reduce energy/lower the melting point of the aluminium oxide

1

(iv)

ions must be mobile

1

(v)

oxide O2 −

1

(i)

near power station (1) electrolysis needs electricity (1) OR good transport system (1) import of bauxite/export of aluminium (1)

2

(ii)

making our resources last longer/cheaper metals/ lower energy costs

1

(i)

conducts heat

(ii)

conducts electricity

(iii)

does not corrode

om

1

QUESTIONSHEET 17

(b)

1 1 1

TOTAL 11

One each for: sodium ----- electrolysis zinc ----------reduction with coke copper ------heat sulphide with oxygen

3

(ii)

most reactive metals need electrolysis least reactive by heating

1 1

(iii)

carbon

1

(i)

displacement/ oxidation – reduction/ reduction

1

(ii)

sodium more reactive than titanium

1

he

(i)

ww w.c

(a)

e.c

(c)

cost of electricity

ctiv

(b)

(i)

ma

(a)

TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 18 1

(ii)

E

1

(iii)

D

1

(iv)

B

1

(i)

heating up incoming air

1

(ii)

Two from: nitrogen, carbon dioxide, carbon monoxide

om

(c)

C

carbon

e.c

(b)

(i)

QUESTIONSHEET 19

ctiv

(a)

2 1

TOTAL 8

nitrogen is very unreactive

(b)

products turn back into reactants

(c)

a catalyst/ iron catalyst

(d)

returned to reaction/recycled/used again

(e)

strong smell alkaline/ red litmus paper turns blue

1 1

(i)

ammonium nitrate

1

(ii)

contain a lot of nitrogen improves crop yield

he

ww w.c

(f)

ma

(a)

1 1 1 1

1 1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 20

(ii)

Two from: on roads in winter, seasoning, preserving food, glazing earthenware, curing bacon

2

(i)

strong alkali

1

(ii)

Two from: soap, paper, dyes, rayon

2

om

1

gas bleach

(ii)

Two from: treating water, swimming pools, making plastics, dyes, hydrochloric acid, solvents, refrigerants,bleaches

ctiv

e.c

(i)

ma

(c)

sodium chloride

he

(b)

(i)

ww w.c

(a)

1 1

2

TOTAL 10

GCSE CHEMISTRY

METALS & THE REACTIVITY SERIES ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 voltmeter

1

(b)

greater difference between the reactivity of the metals the greater the voltage references between more reactive metal & greater voltage

1 1 1

(c)

accept any value between 0.6 and 1.6 volts

1

(d)

stays at 1.6 volts

1

(e)

silver is slightly less reactive than copper

1

(f)

liquid will spill out of the container / not portable

e.c ma

D A B C (2 for all correct, 1 for one mistake)

A = magnesium B = iron C = platinum D = calcium (4 correct – 3 marks, 3 correct – 2 marks 2 correct – 1 mark)

(c)

ww w.c

he

(b)

1

TOTAL 8

ctiv

QUESTIONSHEET 2 (a)

om

(a)

2

3

(i)

2 HCl

1

(ii)

MgCl2 contains Mg2+ formula is MgSO4

1 1

(iii)

magnesium nitrate

1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 3

(ii)

no reaction

1

(iii)

reaction Æ magnesium sulphate + zinc

1 1

(i)

loss of oxygen/gain of hydrogen/gain of electrons

1

(ii)

magnesium + copper oxide Æ magnesium oxide + copper

1

(iii)

magnesium circled

1

(iv)

the minimum energy required for a reaction to happen

(i)

lead oxide/copper oxide

(ii)

calcium oxide/potassium oxide

QUESTIONSHEET 4

1

TOTAL 12

lithium barium magnesium aluminium all correct – 2 marks, 2 correct – 1 mark

ww w.c

(b)

solution aluminium nitrate barium nitrate lithium nitrate magnesium nitrate

(c)

1 1 1

he

(a)

om

1 1

e.c

(c)

reaction Æ zinc sulphate + copper

ctiv

(b)

(i)

ma

(a)

aluminium

barium

2

lithium 9

magnesium

8

8

8

4 correct - 3 marks 3 correct - 2 marks 2 correct – one mark

3

aluminium reacts with oxygen/air forms layer of aluminium oxide coating prevents aluminium from reacting

1 1 1 TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 5

(c)

1

(ii)

lowers melting point of aluminium oxide process uses less energy/cheaper

1 1

(iii)

anode 2O2- Æ O2 + 4e-

1

cathode Al3+ + 3e- Æ Al

1

haematite

(ii)

loss of oxygen/gain of hydrogen/gain of electrons

(iii)

3CO + Fe2O3 Æ 3CO2 + 2Fe

(iv)

road building/fertiliser

e.c

(i)

om

bauxite

ctiv

(b)

(i)

aluminium higher than carbon in series carbon not reactive enough to reduce aluminium oxide

QUESTIONSHEET 6

TEST - use of a named indicator eg.Universal or pH indicator RESULT - correct colour for the indicator used eg.turns blue/purple

ww w.c

he

(a)

ma

(a)

1 1 2 1 1 1

TOTAL 12

1

1

(b)

M2O

(c)

GROUP – 1 REASON - forms compounds with similar formula to group 1 metals/ (accept named metal)/forms single positive ions NOT - reacts violently with water (this could be a group 2 metal)

1

(d)

REACTIVITY SERIES - correct order, placing mancunium at the top REASON - group 1 metals appear at the top of the reactivity series

1 1

(e)

copper + mancunium sulphate

1

(i)

mancunium sulphate

1

(ii)

2 MOH + H2SO4 Æ M2SO4 + 2H2O (1 mark for correct formulae for products) (1 mark for balancing)

2

(f)

1

1

TOTAL 11

GCSE CHEMISTRY


QUESTIONSHEET 7 (i)

iron + aluminium oxide

1

(ii)

2 Al and 2 Fe BOTH REQUIRED

1

(b)

aluminium is more reactive / higher in reactivity series than iron metals will therefore swap places / displacement occurs

1 1

(c)

gives a larger surface area therefore gives a higher rate of reaction / reacts more quickly

1 1

(d)

(i)

copper is less reactive than iron / is lower in the reactivity series therefore no reaction will take place

1 1

magnesium / zinc

1

QUESTIONSHEET 8 measuring cylinder / burette/ pipette

(b)

chemical balance / balance NOT weighing machine or scales temperature would rise brown / pink solid formed solution becomes colourless / blue colour of solution fades

he

(c)

ma

(a)

ctiv

e.c

(ii)

om

(a)

TOTAL 9

1

1 1 1 1

Cu + ZnSO4 BOTH REQUIRED

(e)

some zinc will be left over / unreacted at the end of the reaction / more than enough zinc to react with the copper sulphate

1

(i)

no reaction would take place

1

(ii)

zinc is less reactive than magnesium / magnesium is more reactive than zinc zinc will not be able to displace magnesium

1 1

(f)

ww w.c

(d)

1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 9

D

2

1 1

(d)

C

1

(e)

copper + oxygen Æ copper oxide (1 mark for identifying oxygen as a reactant) (1 mark for identifying the oxide as the sole product)

2

(f)

metal D is very reactive with water metals react more vigorously with acid than with water (references to 'too dangerous' scores 1 mark)

1 1

ww w.c

he

ctiv

REASON - reacts vigorously with water/ most reactive metal

ma

(c)

D B A LEAST REACTIVE C (1 mark for C being placed as least reactive)

1

MOST REACTIVE

om

(b)

ONE FROM: metal A - reaction with air - colour change metal B - reaction with air - colour change metal B - reaction with water - fizzing/bubbles/effervesces metal D - reaction with air - colour change metal D - reaction with water - fizzing/bubbles/effervesces

e.c

(a)

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 10 copper

reacts with steam

iron

vigorous reaction in cold water

magnesium

no reaction with steam or water

potassium

reacts reversibly with steam

om

(a)

(ii)

magnesium/ iron

(i)

hydrogen

(ii)

lighted splint pops/explodes

QUESTIONSHEET 11

(b)

(c)

1 1 1 1 1 TOTAL 8

aluminium zinc iron lead (4 correct – 2 marks, 2 correct – 1 mark)

2

(i)

MgSO4(aq) + Cu(s) Æ Mg(s) + CuSO4(aq)

2

(ii)

Any two from: magnesium dissolves brownish copper metal precipitated blue colour of solution fades

2

(iii)

copper – last/bottom magnesium – first/top

1 1

(i)

no reaction

1

(ii)

reaction Æ aluminium sulphate + iron

1

ww w.c

(a)

ctiv

potassium

ma

(c)

(i)

3

he

(b)

e.c

one per connection

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 12 Any two from: sodium melts/becomes molten ball moves across water quickly increased amount of fizzing

2

(ii)

2Na + 2H2O Æ 2NaOH + H2

1

(iii)

purple/dark blue pH 12 – 14

1 1

(i)

alkali metals

(ii)

have one electron in outer shell

(iii)

reactivity increases down group outer electron becomes further from nucleus nucleus has less force of attraction on outer electron/ increased shielding outer electron is lost more easily

QUESTIONSHEET 13

he

ma

(c)

Any two from: potassium moves across water at increased speed burns with lilac flame sparks/explodes

e.c

(b)

om

(i)

ctiv

(a)

2 1 1 1 1 1 1 TOTAL 13

oxygen and water BOTH REQUIRED

(b)

zinc corrodes instead of the iron NOT forms a protective barrier

1

(c)

zinc is more reactive than iron/ zinc is higher in the reactivity series.

1

(d)

sea water is needed to complete the circuit

1

(e)

arrow points away form the zinc block

1

(f)

PREDICTION : iron would rust faster REASON : iron is more reactive than copper and so will corrode first

1 1

(g)

nails placed in salt water and in deionised water some form of observation or measurement of rusting after a period of time use of 'fair' test or comparison between the two results

1 1 1

ww w.c

(a)

1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 14

(b)

1

TWO FROM : brown solid formed blue solution will fade/become colourless zinc dissolves

2

(ii)

copper + zinc sulphate BOTH REQUIRED

1

(i)

13oC

1

(ii)

exothermic

(iii)

TWO FROM: add greater mass of zinc use a more concentrated solution of copper sulphate use a more reactive metal than zinc/accept a named metal

(i)

ctiv

e.c

(c)

the less reactive metals were discovered first or earlier

om

(a)

ma

QUESTIONSHEET 15

1

2

TOTAL 8

brown solid is copper metal magnesium is more reactive than copper

1 1

(b)

no reaction takes place copper is less reactive than zinc

1 1

(c)

THREE FROM : carbon is more reactive than iron carbon will displace iron from its oxide forming iron metal carbon is less reactive than aluminium carbon and aluminium oxide will therefore not react

3

(d)

zinc is more reactive than hydrogen zinc will displace hydrogen from an acid to form hydrogen gas copper is less reactive than hydrogen

1 1 1

(e)

stability of carbonates is linked to the position of metals in the reactivity series carbonates of metals that are lower decompose more easily

1 1

ww w.c

he

(a)

TOTAL 12

GCSE CHEMISTRY


QUESTIONSHEET 16 bubbles of gas / fizzing / effervescence/ iron dissolves

1

(b)

aluminium metal has a layer of oxide present this makes it resistant to attack / is a protective layer /prevents reaction

1 1

(c)

students were investigating the effects of acid rain this contains sulphuric acid / formed from sulphur dioxide

1 1

(i)

lead and copper nitrate (ANY ORDER - 1 mark each)

2

(ii)

brown / pink solid or deposit

1

(iii)

lead + copper nitrate → copper + lead nitrate

(iv)

lead has displaced the copper in the compound (accept replaced or changed places with)

e.c

ctiv

(d)

sodium

(c)

mercury

(d)

sodium

(e)

magnesium

(f)

iron

(g)

zinc

(h)

sodium

(i)

calcium

he

(b)

ww w.c

silver

ma


om

(a)

1 1

TOTAL 10

1 1 1 1 1 1 1 1 1 TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 18 iron aluminium oxide

1 1

(b)

energy is given out in the reaction / reaction is exothermic temperature rises above 1500oC to melt the iron

1 1

(c)

increases the surface area reaction rate is increased / reaction happens faster

1 1

(d)

to allow the molten iron to run into the gap between the rails

1

(e)

clay is able to withstand the high temperatures reached

(f)

aluminium is more reactive than iron copper is less reactive than iron displacement only occurs when the metal is more reactive

ctiv

e.c

om

(a)

(c)

(d)

TOTAL 11

1

(i)

gain oxygen/lose hydrogen/lose electrons

1

(ii)

magnesium + oxygen Æ magnesium oxide OR copper + oxygen Æ copper oxide

1

ww w.c

(b)

magnesium copper silver

1 1 1

he

(a)

ma

QUESTIONSHEET 19

1

(i)

copper becomes black/coated in silver

1

(ii)

copper more reactive than silver displaced silver from solution

1 1

(i)

no visible reaction

1

(ii)

copper is less reactive than magnesium cannot displace magnesium

1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 20 1

(ii)

magnesium hydroxide (allow oxide)

1

(i)

hydrogen

1

(ii)

Two from: calcium, zinc, iron, lead, nickel

2

copper/silver/gold/platinum

1

e.c

gold & silver are unreactive do not tarnish easily/retain shine iron would rust/corrode

ctiv

(c)

ma

(iii)

om

hydrogen

he

(b)

(i)

ww w.c

(a)

1 1 1 TOTAL 9

GCSE CHEMISTRY

NON-METALS ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 increases

1

(ii)

decreases

1

(b)

105 kJ per mole

1

(c)

while bond length increases bond energy decreases

1 1

(d)

none because astatine is likely to be insoluble

1 1

(e)

C1, Br, I, At or if one out of order

(f)

no as bond energy decreases expect reactivity to increase

e.c ctiv

QUESTIONSHEET 2

om

(i)

ma

(a)

2 1 1 1 1 TOTAL 12

sulphur dioxide

(b)

-10oC

(c)

the gas has been dried pH paper reacts to aqueous solutions

(d)

pH falls below 7 / paper becomes yellow/orange/red

1

(e)

2SO2 + O2

2

(f)

catalyst

(g)

heat given out

(h)

SO3 + H2O → H2SO4

2

(i)

the bulk of the liquid absorbs the heat so no spray is caused

1 1

ww w.c

he

(a)

2SO3

1 1 1 1

1 1

TOTAL 13

GCSE CHEMISTRY


QUESTIONSHEET 3 (i)

yellow/green gas

1

(ii)

iron(III) chloride

1

(iii)

2Fe(s) + 3Cl2(g) → 2FeCl3(s)

2

(iv)

chlorine is poisonous

1

(b)

less vigorous

1

(c)

(i) 2Na(s) + Br2(l) → 2NaBr(s)

om

(a)

e.c

(ii) potassium and fluorine potassium is the most reactive metal (1), fluorine the most reactive non-metal (1)

ctiv

QUESTIONSHEET 4

2 1 2

TOTAL 11

glowing splint - relights in oxygen but not in nitrogen

2

(ii)

flame - 'pop' noise in hydrogen only or litmus paper goes red and then bleached in chlorine only

2

(iii)

lime water goes white/milky in carbon dioxide only

3

(iv)

litmus goes blue in ammonia solution only

3

he

ma

(i)

ww w.c

[ The above will perhaps be the most common answers - there are alternative answers!]

TOTAL 10

QUESTIONSHEET 5 (a)

(i) S mass(g) 3.2 moles: 3.2/32=0.1 ratio 1 So formula is SO2 (ii)

(b)

(c)

: : : :

O 3.2 3.2 / 16 = 0.2 2

oxygen

1 1 1 1

(i) a reaction that can go backwards or forwards

1

(ii) SO2 + 2O2

2

2SO3

in oxygen there is less distance between the nucleus and the outer shell/orbit (1), therefore more easy to gain electrons (1)

2 TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 6 1 1

(i)

nitrogen

1

(ii)

nitrogen

1

(iii)

potassium

1

(c)

magnesium

1

(d)

Mr for NH4NO3 = 14+4+14+48 = 80 80 g NH4NO3 contains 28 g nitrogen 28 × 100 = 35% N content = 80

QUESTIONSHEET 7 (a)

2, 8, 5 xx

(c)

(d)

ww w.c

x x H o P o H xo H

(b)

ctiv

the nitrate also supplies potassium

ma

(e)

he

(b)

om

N,P,K are the chemical symbols of nitrogen, phosphorus, potassium fertilisers contain these

e.c

(a)

1 1 1 1 TOTAL 10

1

2

Formula PH3

1

(i)

gas

1

(ii)

covalent bonding weak attraction between molecules

1 1

fertilisers

1 TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 8 appearance: thin/ mobile amber/yellow

1

structure: short chains of sulphur atoms

1

appearance: liquid becomes thicker

1

structure: chains of sulphur atoms tangle

1

(b)

allotropes

1

(c)

must have cooled slowly trapping crystals under surface needle structure disappears/ become lozenge-shaped

(ii)

none

e.c

(i)

ctiv

(d)

om

(a)

QUESTIONSHEET 9 points plotted correctly best fit curve

(b)

support

(c)

appears to help prevent tooth decay

(d)

involves enforced "mass medication" / too much fluoride is harmful

(e)

tablet form toothpaste

ww w.c

he

ma

(a)

1 1 1 1 TOTAL 9

1 1 1 1 1 1 1 TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 10 methane, ammonia, nitrogen, oxygen, carbon dioxide, sulphur dioxide

6

(b)

points correctly plotted best fit curve

1 1

(i)

0.86 dm3

1

(ii)

0.60 dm3

1

(i)

46 g

1

(ii)

N = 14, & O = 16, so sum = 30 to make 46 one more O is needed so formula = NO2

(d)

e.c

(c)

om

(a)

HF = 1 + 19 = 20 line drawn on graph from 20 on x axis to curve line drawn on graph from curve to y axis from graph, volume = 1.2 dm3

ma

ctiv

(e)

QUESTIONSHEET 11

TOTAL 19

(ii)

two atoms per molecule

(iii)

2,8,7.

(iv)

Cl atom gains an electron (1) to become a negative Cl ion/Cl- (1)

2

(i)

At2

1

ww w.c

he

fluorine

1 1 1

(ii) black solid

1

(iii) seven

1

(iv)

H

xx

At xx

xx

(b)

1 1 1 1 1

(i)

xo

(a)

1 1 1

or H-At

Type of bonding – covalent

2 1

TOTAL 11

GCSE CHEMISTRY


QUESTIONSHEET 12 B

1

(i)

A, B & E

3

(ii)

do not conduct heat/not shiny/low boiling point - any two

1

(c)

Type of bonding: covalent/electrons shared by the two non-metals Reason: atoms covalently bonded together give molecules forces of attraction between molecules are weak/molecules are easily seperated

1 1 1

(d)

hydrogen

(b)

om

(a)

1

e.c

[A = sulphur, B = bromine, C = sodium, D = copper, E = hydrogen]

(a)

the existence of an element in two or more forms (i)

he

(2)

(2)

4

(i)

carbon atoms are linked by very strong covalent bonds in a three-dimensional/ macromolecular structure

(ii)

carbon atoms use only three of their outer electrons to form covalent bonds remaining electrons are delocalised/ can move along the layers and therefore conduct electricity

ww w.c

(c)

1

(ii)

ma

(b)

ctiv

QUESTIONSHEET 13

TOTAL 9

1 1 1 1

TOTAL 9


(i) (ii) (iii) (iv)

bromine carbon chlorine sulphur or oxygen

1 1 1 1

(b)

NH3 covalent

2

(d)

sulphur

1

(d)

X = sulphur or oxygen Y = carbon

1 1 TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 15

(b)

(i) (ii) (iii) (iv)

(c)

no smell/tasteless/colourless/almost insoluble in water/lighter than air - any two

2

zinc (1) hydrochloric acid (1) [and many more!] make sure that there is no air/oxygen left in the apparatus before igniting water anhydrous copper sulphate (1) goes from white to blue (1) or anhydrous cobalt chloride (1) goes from blue to purple (1)

2 1 1

helium

1

om

(a)

(a)

(i) C (ii) B

A

(b)

(i)

iodine (ii) diamond (iii) sodium chloride

(c)

(i)

the breaking down of a substance by electricity

(ii)

2 in front of the Cl (1), + 2e- (1)

he

QUESTIONSHEET 17

ma

-

ctiv

(iii)

e.c

QUESTIONSHEET 16

2

TOTAL 9

3 3 1 2

TOTAL 9

water vapour

(b)

helium

(c)

becomes solid

(d)

nitrogen

(e)

fractional distillation

1

(f)

N = 78%, O = 21%

2

(g)

some oxygen dissolves in water nitrogen does not

1 1

(h)

less of it in air

1

(i)

carbon dioxide is soluble in water

1

ww w.c

(a)

1 1 1 1

TOTAL 11

GCSE CHEMISTRY



A = carbon, B = lime water/calcium hydroxide

2

(b)

C = decomposition, D = photosynthesis, E = oxidation/burning

3

(c)

heat (1) with carbon (1)

2

(d)

fizzy drinks/fire extinguisher/'dry ice' - any one

1

(e)

CO2 (1) 2

2

(f)

CO2 has a simple molecular structure, SiO2 has a giant molecular structure

e.c

om

2 (1)

QUESTIONSHEET 19 (i)

O,

(b)

(i)

carbon (ii)

K sodium

(i) (ii)

two two

(e)

(i) (ii)

three seven

he

(d)

ma

iron and sulphur sodium, oxygen and hydrogen potassium chloride

ww w.c

(c)

(ii)

ctiv

(a)

2

TOTAL 12

1 1 1 1 1 1 1 1 1

TOTAL 9


(i)

increase

(ii)

increase

(i)

gas

(ii)

gas

1

(iii)

liquid

1

(iv)

solid

1

(c)

solid

1

(d)

insoluble

1

(e)

F, C1, Br, I, At 1 if 1 out of order

2

(b)

1 1 1

TOTAL 10

GCSE CHEMISTRY

PRODUCTS FROM OIL ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1

(i)

3

compounds with different numbers of carbon atoms have different boiling points heating vaporises crude oil different compounds condense at different temperatures

3

(ii)

gasoline

(iii)

naphtha compounds containing only the elements carbon & hydrogen

QUESTIONSHEET 2

1 1 1

TOTAL 10

(ii)

contains oil/stop oil running about/safety

1

very high dark yellow does not burn

1 1 1

(ii)

A Any two from low b.p./volatile easy to burn clean flame

he

(i)

ma

distillation

(b)

(c)

1

(i)

ww w.c

(a)

e.c

(c)

ctiv

(b)

Any three from: bodies of sea creatures that died millions of years ago decayed anaerobically under high temperature and pressure

om

(a)

C high viscosity

1

1

2 1 1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 3 a compound containing carbon & hydrogen only

1 1

(b)

Any two from: compounds have same general formula physical properties show gradation chemical properties are similar

2

C6H14

1

(c) (d)

(i)

om

(a)

H H

H

H

H H

C

C

C

C

H

H

H

H

H

H

H

C

C

C

H

H

H

ctiv

H

C

H

e.c

H

H

straight chain version

(iii)

Any two from: has greatest contact with neighbouring molecules therefore greater intermolecular forces of attraction greater forces mean more energy/heat needed to separate molecules

ww w.c

QUESTIONSHEET 4

he

ma

(ii)

2

1

2

TOTAL 10

(a)

fractional distillation

1

(b)

cracking

1

(c)

polymerisation

(d)

(e)

H

H

C

C

H

H

1

n

single bond indication of long chain

1 1

non-biodegradable/stays in ground for a long time toxic fumes when burnt

1 1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 5 contains carbon – carbon double bond

1

(b)

CnH2n

1

(c)

Any two from: 300oC/raised temperature/heat 60 atmospheres/high pressure phosphoric acid/catalyst

2

H

C

C

H

H

OH

H

Cl

H

C

C

C

C

H

H

H

H

ma

Cl

1

1 1

ctiv

shake each gas with bromine water bromine loses colour with ethene/not with ethane

he

(f)

H

ww w.c

(e)

H

e.c

(d)

om

(a)

2

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 6 (a)

(i)

high temperature named catalyst (aluminium oxide/silicon dioxide/broken pot)

1 1

(ii) water heat

liquid paraffin in mineral wool catalyst heat collection over water

ctiv

ma

saturated have only carbon-carbon single bonds unsaturated have at least one carbon-carbon double bond

he

(b)

product is gas, starting material is liquid

ww w.c

(iii)

om

pieces of broken porcelain

e.c

mineral wool soaked with liquid paraffin

1 1 1 1 1 1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 7 (i) H

H

C

C

H

H

H

1

has only carbon-carbon single bonds

1

(iii)

needs a double bond to form polymers

1

(i) H

H

H

H

H

C

C

C

C

H

H

H

H

H

H

H

H

C

C

C

C

H

(ii) H

H

H

H

C

C

C

C

H

C2H5

H

C2H5

he

ma

or

H

H

CH3

CH3

CH3 CH3

C

C

C

C

H

H

H

H

1

1

(i)

cups/electrical fittings/kettles

1

(ii)

heat sample of the plastic if it melts it is thermoplastic if it chars it is thermosetting

1 1 1

ww w.c

(c)

or

om

(ii)

e.c

(b)

H

ctiv

(a)

TOTAL 9

QUESTIONSHEET 8 (a)

(i) (ii) (iii) (iv) (v) (vi)

1,2-dibromoethane hydrogen nickel/platinum phosphoric acid/sulphuric acid poly(ethene) /polythene ethanol

1 1 1 1 1 1

H2O Æ

2

(b)

C2H4

(c)

making margarine

+

C2H5OH

1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 9 (a)

(b)

(i)

pentane

1

(ii)

C8H18

1

(i) 180

X

160

X

140

X

om

120 100 80

40

X

20 0

1

2

3

X4

5

6

7

- 40

X

- 60 - 80

- 120

X

- 180

H

sensible scales axes labelled + units points plotted correctly smooth curve drawn through points

1 1 1 1

99oC (+/- 1oC)

1

H

H

C

C

H

H

ww w.c

(c)

10

he

- 140

(ii)

9

ma

X - 100

- 160

8

ctiv

- 20

e.c

X

60

H

H

H

C

C

C

H

H

H

H

H

H

H

H

H

C

C

C

C

H

H

H H

H

C H

C

H H

H

H H

H

C

C

C

H

H H H

H C

H

H

3

TOTAL 10

GCSE CHEMISTRY



H

H

H

H

H

H

C

C

C

C

C

C

H

H

H

H

H

H

2

e.c

om

(b)

it is light/low density strong

(d)

poly(ethene) is stronger than paper can be mass produced/ethene is now readily available

(ii)

poly(phenylethene) H C H

(b) (c)

(d)

C6H5 H C

ma

ww w.c

(i)

he


1 1

ctiv

(c)

2

H

1 1

TOTAL

8

1

1

double bond

1

(i)

flexible electrical insulator

1 1

(ii)

rubber perishes/cracks in time poly(chloroethene) is fire-resistant

1 1

non-biodegradable toxic fumes when burned

1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 12 A poly(propene) B

H

CH3

C

C

H

H

1

1

n

om

(a)

D

F

F

C

C

F

F

1

e.c

C tetrafluoroethene

1

the simplest compound from which a polymer is made

1

(c)

a molecule/compound made by joining thousands of monomers

2

(d)

C2 F 4

1

(e)

it does not rust/lighter/lower density

1

TOTAL

he

QUESTIONSHEET 13

ma

ctiv

(b)

9

alkanes

(b)

ethene and propene

2

(i)

C8H18

1

(ii)

octane

(c)

(d)

(e)

1

ww w.c

(a)

1

Two from: makes use of less useful fractions produces more petrol produces alkenes/raw materials for the petrochemical industry

2

Two from: poly(ethene) ethanol bromoethane ethane-1, 2-diol

2

TOTAL

9

GCSE CHEMISTRY


QUESTIONSHEET 14 water

1

(b)

turn cloudy/milky

1

(i)

carbon

1

(ii)

incomplete combustion

1

(iii)

carbon monoxide

1

(c)

om

(a)

(b)

C2H4 (i)

oxygen

(ii)

C3H7

+

C

H2O Æ

O

C2H5OH

ctiv

(a)

CH3

(d)

he

2 1

1

2

Against Two from: can have side effects lack of consumer choice can lead to bad food being sold

2

(i)

sugar cane needs warm climate to grow Brazil’s climate is more suitable that Britain’s

1 1

(ii)

people may drink it

1

solvent

1

ww w.c

(c)

For Two from: help to preserve food help food processing attractive colours

ma

O

(iii)

e.c

QUESTIONSHEET 15

TOTAL 5

TOTAL 12

GCSE CHEMISTRY


QUESTIONSHEET 16 (a) H

H

H

H

H

C

C

C

C

H

H

H

H

H

1

C5H12 C6H14 H

H

H

H

C

C

C

C

C

C

H

H

H

H

H

H

keep it cool keep away from flames & sparks

(c)

they would tend to boil off together

(i)

13% (± 2%)

(ii)

16% (± 3%)

(iii)

24% (± 3%)

(b)

liquid

(c)

11%

ww w.c

(a)

he

QUESTIONSHEET 17

H

ma

(b)

om

H

e.c

H

ctiv

H

1 1

1 1 1 1

TOTAL 7

1 1 1 1 1

TOTAL 5

GCSE CHEMISTRY


QUESTIONSHEET 18 a substance which helps in cleaning processes

1

(ii)

Two from: if not, will stay in water causing rivers to foam harming aquatic life

2

(i)

chromatography

1

(ii)

ink would run in solvent

1

(iii)

yellow

(iv)

orange

om

(b)

(i)

e.c

(a)

TOTAL 7

(i)

jet aeroplane fuel

1

(ii)

petrol

(iii)

petroleum gas

ma

1 1 1 1

he

(b)

1

guttering – easily moulded carrier bags – can be coloured or lightweight combs – easily moulded sandwich bags – non-toxic

ww w.c

(a)

ctiv

QUESTIONSHEET 19

1

1 1

TOTAL 7


C & D (both)

1

(i)

produces carbon dioxide may produce toxic gases

1 1

(ii)

last for a long time/may cause pollution of water supplies eyesore

1 1

(c)

they may melt if they are thermoplastics

1 1

(d)

used to heat homes/factories

1

(b)

TOTAL 8

GCSE CHEMISTRY

RATES OF REACTION ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 (i)

scales plotting all the points accurately drawing a smooth curve ignoring the 6 min point

1 1 1

(ii)

I

1 1 1 1

II

he

ma

ctiv

e.c

om

particles have more energy greater chance of successful collision therefore greater rate of reaction

ww w.c

(iii)

curve drawn to the left of curve A curve to start at 71.00 g and to finish at 70.20 g curve drawn to the right of curve A curve to start at 71.00 g and to finish at 70.60 g

1 1 1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 2 (a)

halve time three times 4 mins

(b)

70

1 1

60

om

40

e.c

Temperature/ 0C

50

ctiv

30

10

0 0

10

20

he

ma

20

30

40

50

60

70

(c)

ww w.c

Time/min

sensible scales correct plotting correct line drawn

1 1 1

impossible to have reaction in zero time too cold and reaction will stop

1 1 TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 3 All state symbols correct: CaCO3(s) + 2HCl(aq) Æ CaCl2(aq) + CO2(g) + H2O(l)

1

(ii)

calcium chloride

1

(iii)

40 + 12 +(3 × 16) = 100

1

(iv)

A Idea that 1 mole / 1 molecule of CaCO3 produces 1 mole / molecule of CO2 mass of 1 mole of CO2 = 44 g

1 1

B 0.44 g / 1% of candidate’s answer to A

1

(i)

would know how much CO2 could be produced if very different result obtained, could indicate error/could be used to monitor reliability of technique

1

in method A, some CO2 would escape before apparatus was placed on balance/ before initial reading could be taken would lead to underestimate of CO2 produced

1 1

ctiv

(ii)

om

(b)

(i)

e.c

(a)

(c)

(d)

1 1

(i)

9Z

1

(ii)

9X

(iii)

9Y

(i)

St Paul’s

1

(ii)

concentration affects rate of reaction St Paul’s is fastest

1 1

shine lamp through beaker set photocell on other side time how long it takes for motor to stop

1 1 1

1

ww w.c

(b)

sulphur is produced clouds up the beaker/ sulphur is insoluble

he

(a)

TOTAL 10

ma

QUESTIONSHEET 4

1

1

M

uv lamp

photo cell

motor

1

TOTAL 12

GCSE CHEMISTRY


QUESTIONSHEET 5 1 1

(ii)

enzymes

1

(i)

sample at 80oC

1

(ii)

enzyme denatured at 80oC leaving the reaction without a catalyst so very slow

1 1 1

(iii)

sample at 40oC

(iv)

reaction is fastest at this temperature/ reaction is slower at lower temperatures most starch digested

1 1

(v)

iodine

1

om

a substance which speeds up a reaction but is not used up/ still present at the end of the reaction

e.c

(b)

(i)

ctiv

(a)

ma

QUESTIONSHEET 6

1

TOTAL 11

fizzes / bubbles/ gradually disappears

1

(b)

40 cm3 = 4 cm3 s-1 10 s

1

he

(a)

much slower fewer particles, so fewer collisions

(d)

increase temperature / heat it change surface area of magnesium → powder 40 moles of hydrogen = 24,000 -3 = 1.67 × 10

(e)

ww w.c

(c)

1 1 1 1

1 1 TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 7 yellow precipitate/ goes cloudy

1

(b)

sodium chloride, water, sulphur dioxide (any 2)

2

(c)

increase concentration of either reactant more particles closer together/ more collisions

1 1

(i)

plot of either volume of Na2S2O3 or water v time points plotted smooth curve

1 1 1

(ii)

concentration

(iii)

to keep concentration of acid constant

(iv)

goes cloudy/ solid forms

e.c

1 1 1

TOTAL 11

ctiv

(d)

om

(a)

ma

QUESTIONSHEET 8

add universal indicator solution/paper/test with pH meter universal indicator turns orange/pink/pH falls

1 1

(b)

the amount/mass of lactic acid produced in 1 second/specified time

1 1

(c)

bacteria produce an enzyme/biological catalyst

(d)

statements or diagrams showing: lactose molecules colliding with enzyme molecules lactose and enzyme molecules bonded together lactic acid molecules released from enzyme molecules

1 1 1

(e)

the concentration of lactose decreases/ the lactic acid destroy the enzyme/kills the bacteria

1

(f)

the rate of reaction decreases because the high temperature destroys the enzyme/kills the bacteria

1 1

ww w.c

he

(a)

1

TOTAL 11

GCSE CHEMISTRY


QUESTIONSHEET 9

(c)

1 1 1

(i)

take value from graph (about 21)

1

(ii)

reaction is so fast

1

(i)

hydrogen

1

(ii)

‘pops’ with lighted splint

om

(b)

pxes labelled points plotted smooth curve

TOTAL 8

creates larger surface area of catalyst

(ii)

rate of reaction increases as temperature rises

(i)

reactants stick to surface of catalyst products separate from catalyst after reaction heavy metals block surface to reactants

1 1 1

(ii)

lead is a heavy metal would ruin catalyst

1 1

he

ma

(i)

ww w.c

(b)

ctiv


2

e.c

(a)

1 1 1

TOTAL 8

QUESTIONSHEET 11

2H2O(l) Æ 2H2O(l) + O2(g) formulae correct balancing

1 1

(i)

manganese(IV) oxide / manganese dioxide

1

(ii)

lowers activation energy provides surface for reaction

1 1

(iii)

weigh before and after then test its catalysing properties again

1 1

(a)

(b)

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 12

(i)

hydrogen

1

(ii)

lighted splint produces pop / explosion

1 1

(iii)

Zn + 2HCl Æ ZnCl2 + H2 (formulae – 1, balancing – 1)

2

(i)

rate increased/faster

(ii)


(iii)


om

(c)

1 1

e.c

(b)

measure loss of mass as gas lost over a period of time

QUESTIONSHEET 13

ctiv

(a)

1 1 1

TOTAL 10

pressure forces gases into smaller space molecules more likely to collide

(b)

large surface area of powder can create explosions when it burns/ causes very rapid combustion

(c)

in less than one minute/faster than ribbon

1

(d)

heat gives molecules more energy collisions more likely to produce reaction

1 1

(e)

cooling slows down reactions but does not stop them

1 1

ww w.c

he

ma

(a)

1 1 1 1

TOTAL 9


(b)

CO = carbon monoxide NOx = oxides of nitrogen CH = hydrocarbons

1 1 1

(i)

C

1

(ii)

carbon monoxide

1

(iii)

oxides of nitrogen

1 TOTAL 6

GCSE CHEMISTRY



(i)

steeper line same volume of oxygen

1 1

(ii)

much steeper line same volume of oxygen

1 1 (ii)

(i)

60

90

more gas produced with Y catalyst does not affect outcome of reactions

(c)

some Y used up catalysts are not used up

(b)

oxygen

(c)

(d)

ma

ww w.c

H2O2

he


ctiv

(b)

time in seconds

e.c

30

om

volume of gas

1 1 1 1

TOTAL 8

1 1

(i)

susbtance which speeds up a reaction but does not get permanently used up/ can be recovered unchanged at the end

1 1

(ii)

A does not change speed/rate

1 1

(iii)

C changes speed the most

1 1

5g

1 TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 17

3

(b)

not enough activation energy supplied by a match heat from the match is conducted away by the rest of the tree

1 1

(c)

dust has greater surface area burns more easily

om

Three from: add catalyst heat/warm reaction use higher concentration of reactants use solid reactants with greater surface area / stir more increase pressure of gaseous reactants

e.c

(a)

(ii)

B

(i)

60 cm3

(ii)

20 s 66 cm3

(c) (d)

ma

D

he

(b)

(i)

(i)

66 cm3

(ii)

the same

ww w.c

(a)

ctiv

QUESTIONSHEET 18

1 1 TOTAL 7

1 1 1 1 1 1 1 TOTAL 7


(b)

(i)

(ii) (c)

Two from: (gas) syringe, measuring cylinder, burette

2

Three from: use same sized pieces of magnesium/ use same mass of magnesium use same volume of acid keep temperature the same stir the same amount

3

stop clock

1

balance reading to 2 decimal places

1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 20 One mark for each of the following (in correct order)

he

ma

ctiv

e.c

om

joules kilojoule exothermic endothermic catalyst increased surface area photography/sunburn light

ww w.c

(i) (ii) (iii) (iv) (v) (vi) (vii) (viii) (ix)

1 1 1 1 1 1 1 1 1 TOTAL 9

GCSE CHEMISTRY

REACTIONS & FORMULAE ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 1

(ii)

Li/Na/K/Cu

1

(i)

Al3+

1

(ii)

Cl

(iii)

AlCl3

(i)

covalent

(ii)

CCl4

1

om

1

xx H

x•

(iii)

-

N x• H

H

e.c

(c)

lose one or more electrons

(1 for bond pairs, 1 for lone pair)

ctiv

(b)

(i)

x•

(a)

QUESTIONSHEET 2

(ii)

thermal decomposition

(i)

100

(ii)

Mr of CaO = 56 56 t CaO produced from 100 t calcium carbonate 280 t CaO produced from 500 t calcium carbonate

ma

CO2

he

(b)

(i)

ww w.c

(a)

1 1

2

TOTAL 9

1 1 1 1 1 1

TOTAL 6

QUESTIONSHEET 3 (a)

2 and 2

(b)

mass of magnesium = 44.9 - 40.1 = 4.8 g mass of magnesium oxide = 48.1 - 40.1 = 8.0 g so, mass of oxygen = 8.0 - 4.8 = 3.2 g moles of oxygen = 3.2/16 = 0.2 moles of magnesium = 4.8/24 = 0.2 ratio Mg:O = 1:1 therefore MgO

1 1 1 1 1 1 1

TOTAL 7

GCSE CHEMISTRY


QUESTIONSHEET 4 (a)

(i)

to condense water

1

(ii)

find boiling point/boiling point is 100oC/ find freezing point/freezing point is 0oC/ blue cobalt chloride paper goes pink

1

Note: Cobalt chloride paper test only shows the presence of water, not that the substance is water. It could be dilute acid, salt solution etc. 2.5 - 1.6 = 0.9 g

(ii)

0.9 / 2.5 = 36%

(i)

dehydration

(ii)

CuSO4 + 5H2O

1

om

(c)

(i)

∏ CuSO4.5H2O

QUESTIONSHEET 5

1 1 1 1 1

TOTAL 8

23 + 14 + (3 × 16) = 85

(ii)

14 + (4 × 1) + 14 + (3 × 16) = 80

(i)

14/85 × 100 = 16.5%

(ii)

28/80 × 100 = 35%

1 1

(c)

ammonium nitrate

1

(d)

Two from: alkaline/gas/poisonous/very soluble/smelly

2

(b)

he

(i)

ww w.c

(a)

ma

ctiv

(iii)

e.c

(b)

1 1

1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 6 3.5/14 = 0.25 4/16 = 0.25 NO

1 1

(ii)

50/16 = 3.1 SO2

1 1

(iii)

39/39 = 1 1/1 = 1 12/12 = 1 48/16 = 3 KHCO3

1 1

(iv)

mass of oxygen = 16.0 − 11.2 = 4.8 4.8/16 = 0.3 11.2/56 = 0.2 Fe2O3

1 1 1

(i)

4.04/1 = 4.04 24.24/12 = 2.02 71.72/35.5 = 2.02 ratio of H:C:Cl = 2:1:1 CH2Cl

1 1 1

(ii)

relative mass of CH2Cl = 49.5 99/49.5 = 2 therefore C2H4Cl2

1 1

QUESTIONSHEET 7 (a)

(c)

om

e.c

ctiv

TOTAL 14

1

(i)

copper(II) chloride

(ii)

copper and chlorine

(iii)

bleaches moist indicator paper

1 1

(i)

copper

1

(ii)

water

(iii)

CuO + H2 → Cu + H2O

1

(iv)

reducing agent

1

ww w.c

(b)

copper(II) oxide

50/32 = 1.5625

ma

(b)

(i)

he

(a)

1 2

1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 8 to allow you to find mass of substances in it

1

(ii)

125.9 - 117.8 = 8.1 g

1

(iii)

124.7 - 117.8 = 6.9 g

1

(iv)

8.1 - 6.9 = 1.2 g

1

(v)

1.2/8.1 × 100 = 14.8%

1 1

(d)

208

(ii)

18

e.c

(i)

moles of BaCl2 = 6.9/208 = 0.0332 moles of water = 1.2/18 = 0.0667 ratio of 1:2 therefore x = 2

QUESTIONSHEET 9 precipitation reduction endothermic reversible decomposition oxidation displacement combustion

ww w.c

(a) (b) (c) (d) (e) (f) (g) (h)

ma

(c)

heat the crucible again cool and reweigh repeat until weight is constant

ctiv

(b)

om

(i)

he

(a)

1 1 1 1 1 1 1 1

TOTAL 14

1 1 1 1 1 1 1 1

Note: In a question of this type it is not necessary to use all the available terms. Sometimes, a term will be required more than once.

TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 10 energy/ heat transferred to surroundings

1

(b)

Ca(OH)2

1

(c)

neutralise acidity in lakes/soil/swimming pools

1

(d)

bubble carbon dioxide through it

1

(e)

heating it strongly

1

(f)

compounds can be formed from each other any substances added are given off at a later stage

1 1

e.c

om

(a)

QUESTIONSHEET 11

TOTAL 7

displacement

(b)

c, e, f

(c)

chlorine + potassium bromide → bromine + potassium chloride

(d)

Cl2

(e)

chlorine most reactive, then bromine, last iodine

1

(f)

fluorine displaces chlorine

1

(g)

no reaction

2KCl

+

Br2

he

2KBr ς

ww w.c

+

ma

ctiv

(a)

1 3 1 2

1

TOTAL 10


all are soluble

1

(b)

all are soluble

1

(c)

all except nitrate are insoluble

1 1

(i)

lead carbonate + sodium nitrate

2

(ii)

no precipitate formed/ no reaction

1

(iii)

barium sulphate + sodium chloride

2

barium sulphate is very insoluble not absorbed into bloodstream

1 1

(d)

(e)

TOTAL 11

GCSE CHEMISTRY



0.14 0.13 0.12 0.11

x

0.10

x 0.08 Loss in mass (g)

e.c

0.07

x

0.06

ctiv

0.05 0.04

x

0.03

0.01 10

20

30

ma

0.02

0

om

x

0.09

40

50

60

70

80

90

3

ww w.c

labelled axes sensible scales accurate plotting line of best fit

he

Volume of gas (cm )

1 1 1 1

(b)

student 4

(c)

(i)

38 cm3 (+/- 1 cm3)

1

(ii)

0.02 g (+/- 0.005 g)

1

(i)

find the density of the gas / mass/volume compare to data book

1 1

(ii)

glowing splint relights

1 1

(d)

1

Note: Always include the result of a chemical test. It is not sufficient to say, for example, “Use the glowing splint test”.

TOTAL 11

GCSE CHEMISTRY


QUESTIONSHEET 14 A and D

1

(ii)

rusting requires water/moisture and oxygen/air

1 1

(b)

tube D salt/ions in salt accelerates rusting

1 1

(c)

zinc/magnesium attached to hull/pier zinc/magnesium more reactive than iron corrodes in preference to iron

1 1 1

(i)

alloyed with another metal/electroplated

(ii)

coated in paint/plastic/electroplated

QUESTIONSHEET 15

(c)

iron/steel

(ii)

galvanising

(i)

sulphur dioxide

(ii)

Zn2+

(d) (e)

ma

(i)

ww w.c

(b)

Two from: alloys may resist corrosion alloys may look more attractive alloys have lower meting points

he

(a)

e.c

(d)

om

(i)

1 1

TOTAL 10

ctiv

(a)

2 1 1 1 1

neutralisation

1

(i)

carbon

1

(ii)

ZnO + C →

(iii)

reduction

Zn + CO

1 1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 16 sodium hydrogencarbonate

1

(ii)

acid

1

(iii)

sodium carbonate

1

the acid and carbonate react together and fizz/produce carbon dioxide

1 1

(i)

raising agent because it decomposes when heated to give carbon dioxide gas

1 1

(ii)

does not produce carbon dioxide when heated

1

(b)

(c)

calcium oxide

(ii)

calcium carbonate

ma

(i)

ctiv


om

(i)

e.c

(a)

TOTAL 8

1 1

endothermic

(c)

limestone glowed brightly crumbled

(d)

process is continuous/less energy loss/ time-saving

1

Two from: jobs created money brought into area extension better than starting new quarry

2

Two from: loss of animal habitats eyesore dust noise extra lorries on roads

2

(i)

(ii)

ww w.c

(e)

he

(b)

1 1 1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 18 delivery tube on end of test tube delivery tube through cork end of delivery tube in limewater

1 1 1

(ii)

limewater goes cloudy/milky

1 1

(i)

copper produces a green flame

1

(ii)

dipped in acid

1

(iii)

calcium

(c)

om

(b)

(i)

calcium carbonate

e.c

(a)

A

(ii)

hydrogen

(c) (d)

C (i)

D

(ii)

irritant/harmful

(e)

ma

(i)

ww w.c

(b)

D

he

(a)

ctiv

QUESTIONSHEET 19

hydrogen burns to make water wasserstoff = water maker

1 1

TOTAL

9

1 1 1 1 1 1 1 1

TOTAL 8


(b)

(c)

(i)

C + O2 → CO2

1

(ii)

poisonous

1

(i)

oxygen is removed

1

(ii)

carbon

1

harder lighter in colour rougher texture

1 1 1

TOTAL 7

GCSE CHEMISTRY

THE PERIODIC TABLE ANSWERS AND MARK SCHEMES

QUESTIONSHEET 1 noble/inert/rare gases

1

(ii)

two out of helium, neon, argon, krypton, xenon, radon.

2

(i)

C

1

(ii)

atoms do not combine/monatomic atoms/inert gas so atoms don’t join/ A, B and C show molecules and group 0/8 elements do not form molecules

1

splint goes out/does not burn

1

(c) (d)

all unreactive/stays the same

(ii)

density increases

(iii)

all non metals/stays the same

(iv)

measure the density of each

ma

ctiv

(e)

(i)

om

(b)

(i)

e.c

(a)

QUESTIONSHEET 2

(b)

1 1

TOTAL 10

(ii)

‘A’ has 11 electrons and atomic number of sodium is 11 ‘A’ has one electron in outside shell but ions have full outer shell

1 1

(iii)

one electron in outside shell

1

(i)

charged atom/group of atoms

1

(ii)

K+

1

he

A

(c)

(d)

1

(i)

ww w.c

(a)

1

1

Any two from: very reactive react with air react with oxygen in the air react with water in the air

2

(i)

oxygen (in the air)

1

(ii)

potassium oxide

1

(iii)

potassium + oxygen → potassium oxide

1

(iv)

4K + O2 → 2K2O

2

TOTAL 13

GCSE CHEMISTRY


QUESTIONSHEET 3

(b)

(i)

lithium + chlorine → lithium chloride

1

(ii)

2Li + Cl2 → 2LiCl

1

(i)

group 1

1

(ii)

1

1

(iii)

7

-

x

(c)

+

C1 ς

Li

x

C1

e.c

Li

+

om

(a)

1 1 1

(i)

more reactive

1

(ii)

common/table/cooking salt

he

ma

ctiv

diagram to show: chlorine seven electrons lithium one electron being transferred to chlorine lithium ion one positive charge, chloride ion one negative charge

ww w.c

(d)

1

1 TOTAL 10

GCSE CHEMISTRY


(ii)

sodium ion

1

(iii)

chloride ion

1

(iv)

attraction of opposite charges/ electrostatic attraction

1

(i)

1

(ii)

7

(iii)

3

(iv)

3

(v)

1

(vi)

7

6

(i)

sodium needs to lose one electron to empty outside shell/ to give full/complete outer shell/octet/stable electron arrangement sodium transfers electron to chlorine atom which completes its octet

1 1 1 1

x Na

x

1

(ii)

e.c

om

1

+

C1

ς

ma

(c)

ions

Na+

C1

he

(b)

(i)

one sodium ion electrically balances one chloride ion

ww w.c

(a)

ctiv

QUESTIONSHEET 4

1

TOTAL 16

GCSE CHEMISTRY


QUESTIONSHEET 5

(ii)

antiseptic/put on cuts to kill bacteria/germs

1

(i)

halogens

1

(ii)

non-metal

1

(iii)

non-metal

1

(i)

17 protons in nucleus/17 electrons in uncombined atom

1

(ii)

3

1

(iii)

7

(iv)

sodium iodide NaI

om

1

e.c

(c)

to kill bacteria/germs in water

ctiv

(b)

(i)

QUESTIONSHEET 6

(c)

goes dark

(ii)

photosynthesis/colour fading

(i)

ion/anion/negative ion

(ii)

no

(i)

go dark

(ii)

Ag+(aq) + I (aq) ς AgI(s)

he

(b)

(i)

ww w.c

(a)

ma

(a)

-

1 1 1 TOTAL 10

1 1 1 1 1 3

(2 marks for correct equation; only 1 if ions not shown. 1 mark for state symbols)

TOTAL 8

GCSE CHEMISTRY


QUESTIONSHEET 7 isotopes

1

(ii)

different number of neutrons

1

(iii)

number of protons number of electrons in uncombined atom

1 1

(iv)

35 (neutrons + protons) –17 (protons) 18 neutrons

1 1

(i)

no difference

1

(ii)

Any two from: chemical properties stay the same both elements have 7 electrons/same number of electrons in their outside shell chemical properties depend on number of electrons in outside shell

e.c

1

(iii)

no

(iv)

different masses/physical properties depend on the mass

QUESTIONSHEET 8

(b)

(c)

2 1 1 TOTAL 12

(i)

3

(ii)

second electron shell is full next electron has to go into third shell/one electron in outside shell

1 1

(i)

sodium, magnesium and aluminium/Na, Mg and Al

1

(ii)

go from metallic (left hand side) to non-metallic (right hand side)

1

(i)

6 (electrons)

1

(ii)

sodium oxide: Na2O magnesium oxide: MgO aluminium oxide: Al2O3

3

ww w.c

(a)

ma

(c)

mixture if different isotopes/chlorine-35 and chlorine-37

ctiv

(b)

om

(i)

he

(a)

1

(all three needed for mark)

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 9

(b)

(c)

group 0/8 / noble gases/inert gases

1

(i)

drop/go down/fall

1

(ii)

Any two from: lower down in the group group 0/8 elements get denser as the atomic number increases krypton denser/heavier for the same volume than the gases in the other balloons/air

2

(i)

om

(a)

x

(i)

very light/less dense than air unreactive/does not react with air/non-flammable

1 1

(ii)

unreactive/inert/full outer electron shells won’t react with hot filament of light bulb

1 1

(c)

group 1

(ii)

alkali metals

(iii)

white

ww w.c

(b)

(i)

ma

ctiv

outer shell complete helium does not combine/react with anything


1 1 1

(ii)

he

(d)

e.c

x

TOTAL 11

1 1 1

Any three from: use platinum/nichrome wire clean wire/by dipping in hydrochloric acid and putting into a hot flame dip wire into salt/solution of salt/hydrochloric acid and then salt put into blue flame/hottest part of flame/side of a blue flame look at colour of flame.

3

A = sodium chloride B = lithium chloride C = potassium chloride

1 1 1

TOTAL 9

GCSE CHEMISTRY


QUESTIONSHEET 11

(c)

chlorine, bromine, iodine

1

(ii)

atomic number

1

(i)

7

1

(ii)

molecules

1

(iii)

Any two from: outer shell incomplete each chlorine atom needs one more electron to complete its octet each atom shares one electron

om

(b)

(i)

xx x

(i)

x x

x

e.c

(a)

x xx

1 1

(ii)

gas

1

(iii)

-220 C (accept –200 C to –250 C)

o

ww w.c

he

boils/becomes a gas/vapour

QUESTIONSHEET 12

(b)

o

ma

o

ctiv

diagram to show: two electron shells two electrons in first shell, seven in outside shell

(d)

(a)

2

1 1

TOTAL 11

(i)

colourless

1

(ii)

Any two from: a solid in a liquid very small particles of solid.

2

(iii)

silver chloride

1

(i)

silver nitrate + sodium chloride → silver chloride + sodium nitrate

1

(ii)

(aq)

1

(iii)

(s)

1

(iv)

AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)

2

(c)

B and C

2 TOTAL 11

GCSE CHEMISTRY


QUESTIONSHEET 13 1

(ii)

metals

1

(iii)

Fe = iron, Cu = copper, Zn = zinc

3

(i)

A

1

(ii)

A high melting point/B would melt when the water boiled

1 1

(iii)

hard can be pulled out to make a wire shiny surface that can be polished

1 1 1

QUESTIONSHEET 14

(c)

TOTAL 11

ma

one out of scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, zinc, or between atomic numbers 39-48, 57, 72-80 including silver, gold, platinum and mercury

1

(ii)

limewater

(iii)

lime water went cloudy/milky/white precipitate

1

(iv)

carbon dioxide

1

(i)

copper(II) oxide

(ii)

gas made copper carbonate changed colour

1 1

(iii)

copper carbonate → copper oxide + carbon dioxide

1

(iv)

CuCO3 → CuO + CO2

1

(i)

B

1

(ii)

Any two from: there was a reaction in B/no reaction in A zinc carbonate/transition metal carbonate breaks down on heating sodium carbonate/group 1 metal carbonates do not break down on heating zinc oxide is yellow when hot and white when cold

2

Any two from: A was sodium carbonate sodium carbonate does not break down on heating group 1 metal carbonates do not break down on heating

2

(iii)

he

(b)

(i)

ww w.c

(a)

om

transition elements/ transition metals

e.c

(b)

(i)

ctiv

(a)

1

1

TOTAL 14

GCSE CHEMISTRY


QUESTIONSHEET 15 1

(ii)

blue/green

1

(i)

add a small amount of sodium hydroxide solution colour of precipitate indicates which metal ion is present

1 1

(ii)

A = copper B = green C = iron(III) (all three for 2 marks one or two for one mark)

(i)

Fe2+

(ii)

OH-

(iii)

Fe2+ + 2OH- → Fe(OH)2

ma

ctiv

(c)

transition elements

om

(b)

(i)

e.c

(a)

(b)

(c)

1

TOTAL 9

(i)

2

(ii)

8

(iii)

the number of electron shells

1

(i)

2

1

(ii)

4

(iii)

the number of electrons in the outside shell

1

(i)

6 protons in atom/ in the nucleus 6 electrons in uncombined atom

1 1

(ii)

mass number/ relative atomic mass

1

(iii)

number of neutrons plus number of protons

1

he

(a)

1

ww w.c

QUESTIONSHEET 16

1

1 1

1

TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 17 1

(ii)

One out of: H, N, O, F, Cl, He, Ne, Ar, Kr.

1

(iii)

One out of: Ti, V, Cr, Mn, Fe, Co, Ni, Cu. (allow Sc and Zn)

1

(i)

7

1

(ii)

3

1

(iii)

3

(iv)

7

(i)

inert/noble/rare gases

1

(ii)

unreactive/do not react

(iii)

outer electron shell contains 8 electrons/ complete octet

(e)

1

TOTAL 11

lithium

(ii)

rubidium

(iii)

potassium

1

blue

1

ww w.c

(d)

1

(i)

(b) (c)

1 1


e.c

(d)

1

number of protons/number of electrons in neutral (uncombined) atom

ctiv

(c)

om

One out of: Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge.

ma

(b)

(i)

he

(a)

1 1

(i)

burnt with a ‘pop’/small explosion

1

(ii)

hydrogen

1

(i)

more reactive

1

(ii)

hydrogen and sodium hydroxide

1

Any two from: react with water to give alkalis all metals hydroxides are alkalis hydroxides all dissolve in water to give alkaline solutions

2 TOTAL 10

GCSE CHEMISTRY


QUESTIONSHEET 19

(c)

2

(ii)

expensive/copper compounds are poisonous

1

(iii)

good conductor of electricity ductile/high tensile strength

1 1

(iv)

cars: strong/high tensile strength/(relatively) cheap planes: high density

(i)

speeds up a reaction

(ii)

with transition elements

(i)

positive/cation

(ii)

Cu2+

C or E F or A A D D G E

he

I II III IV V VI VII

ww w.c

(i)

e.c

Fe3+

QUESTIONSHEET 20

om

Any two from: high melting point good conductors of heat strong/high tensile strength

ctiv

(b)

(i)

ma

(a)

1 1 1 1 1 2

TOTAL 12

1 1 1 1 1 1 1

TOTAL 7

GCSE/IGCSE Chemistry Question Bank with Answers

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