Respuestas 8f

Mark Schemes

8F

Quick Quiz 1 Question

Answer

Marks

Matching End of Unit Test marks to NC levels Level

Topic

1

2

3

4

8F a

D

C

D

B

4

8F b

A

C

D

B

4

Marks Cumulative available total

Suggested threshold for achieving level

8F c

A

C

D

D

4

4

3

3

5

8F d

D

B

C

D

4

5

6

9

10

8F e

A

D

D

A

4

6

11

20

16

7

5

25

24

End of Unit Test marks Question Level Answer

Mark scheme

1

4

a aluminium

1 mark

6

b oxygen

1 mark

5

c sulphur 

1 mark

4

d aluminium or glass

1 mark

2

6

Al

1 mark

3

5

a Wood is an insulator/wood does not conduct heat.

1 mark – accept equivalent answers

4

b Shatters easily or is easily broken

1 mark

5

c charcoal has a high melting point.

1 mark – no marks if more than one box has been ticked

6

a copper oxide.

1 mark

6

b oxygen

1 mark

7

c copper oxide weighs more than copper alone

1 mark – also accept ‘oxygen has mass’

6

d three

1 mark

7

e copper, carbon, oxygen

1 mark

6

a element

1 mark

6

b It is a compound/polythene contains two elements/ polythene is made of carbon and hydrogen.

1 mark

5

c renewable

1 mark

6

d Crude oil is non-renewable/fossil fuels are nonrenewable.

1 mark

5

e recycling

1 mark

6

f The bag is being re-used, not recycled/recycling involves melting the bag down and making something new from it.

1 mark

4

5

Exploring Science

edition

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© Pearson Education Limited 2008

8 F

8F

Mark Schemes (continued)

End of Unit Test marks (continued) Question Level Answer 6

8 F

Mark scheme

5

a 100

1 mark

6

b earth and air 

1 mark

6

c water 

1 mark

7

d the smallest particle of an element (that can exist)

1 mark

7

e We now know that there are particles that are smaller than atoms/atoms are not the smallest things possible/ atoms are not indestructible/can be split.

1 mark*

7

f Either 

1 mark* for relevant scientific statement about elements linked to a conclusion about Aristotle’s statement. Yes/no with no supporting reason = 0 marks

 Yes – elements cannot be split up in chemical reactions Or 

No – you can split up elements in a nuclear reaction.

*Award bonus mark(s) (subject to maximum for overall question = 6) for more sophisticated answers, e.g. mention of subatomic particles/protons and electrons, or balanced answer giving both options.

Answers to Quick Check activities Quick Check

Answers

8Fa

Possible answers: 1 The electric cell (battery) was invented about 200 years ago … and metals like sodium and calcium were discovered soon after; therefore only the less reactive metals were known before 1800. 2 Scientists used to think that lime was an element … because they couldn’t split it up using heat or other chemicals; so it was listed in Lavoisier’s table. 3 Elements like gold and silver have been known about for thousands of years … however other metals have only discovered more recently; because they are found naturally in the environment. 4 Elements like copper and tin are fairly easy to get out of rocks … such as malachite and haematite; but sodium and aluminium are not. 5 There are only 117 different elements … however there are millions of compounds; which can be grouped into metals and non-metals.

8Fb

1 A true; B true (at KS3 level – unless a pupil has a knowledge of neutrons and isotopes); C false – Steel is a mixture; D true; E true; F false (there are 117/ more than 90 elements); G false (the symbol for iron is Fe); H true 2 B explains A; D explains why C is false, and the corrected version of  C is explained by D; corrected F does not explain E; H explains the correct version of G (in part – the Latin derivation is more relevant than the French)

Exploring Science

edition

188

© Pearson Education Limited 2008

8F

Mark Schemes (continued)

Answers to Quick Check activities (continued) Quick Check

Answers

8Fc

Possible answers: 1 What type of element is found on the right-hand side of the periodic table? 2 Why is copper used in electrical cables? 3 What type of substance is shiny and conducts electricity? 4 What observation would suggest that gold and silver are both metals? 5 What word beginning with ‘f’ means ‘bendy’? 6 What arrangement is used to show all the chemical elements? 7 Melting point, colour and density are three examples of …? 8 What name do we give to the temperature at which a solid turns into a liquid? 9 What word beginning with ‘i’ means the same as non-conductor? 10 Which is the only metal that is a liquid (at room temperature)?

8Fd

1 A; 2 C; 3 A; 4 B; 5 C; 6 C; 7 B; 8 B; 9 B; 10 B; 11 A; 12 A; 13 B; 14 C; 15 B.

8Fe

1 An element is made up of atoms which are all the same. 2 The metals are on the left (and centre) of the table and the non-metals are on the right. 3 Bronze should not be circled. 4 The handle is made of a good insulator (non-conductor) so that you don’t burn yourself. 5 The glass is collected, cleaned and then re-filled/used again. 6  magnesium + oxygen

magnesium oxide

7 Three (carbon, chlorine, fluorine) 8  CFCl3 9 They damage the ozone layer/upper atmosphere.

Exploring Science

edition

189

© Pearson Education Limited 2008

8 F