(a) _________________and ____________________ are found in the nucleus of an atom. (b) __________________ surrounds the nucleus. (c) The nucleus has ____________________ charge due to the positively-charged protons in it. (d) Number of proton = number of electron. Hence, an atom is __________________.
__________________ are neutral particles made up of __________or ___________ atoms.
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2. Identify the diagrams below. State whether the following is an atom or a molecule.
What is an element and compound? 1. Complete the following with the correct description. Element
Compound
a) Matter made up of more than one type of atoms chemically combined. ___________________ b) Matter that made up of one type of atom only. __________________ 2. Decide whether the following substances are element (E) or compound (C). Substance (a) Carbon dioxide (b)Helium (c)Air (d) Sodium (e) Mercury (f) Iron oxide (g) Oxygen (h) Silicon (i) Glucose (j) Nitrogen dioxide
Element (E) or compound(C)
3. Match the following with the correct description.
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Periodic Table 1. All matter found in the Periodic Table are ___________________. 2. All the elements in the Periodic Table are arranged according to the ___________________. 3. The number of_____________ in an atom is called atomic number. 4. The atomic number is_____________ for each element. 5. Each element can be represented using its ________________. Element Oxygen Carbon Iron Magnesium
Chemical symbol
6. Elements in Periodic Table can be divided into ______________ and ___________________. 7. The diagram below shows a Periodic Table. Complete the label on the diagram with following words.
Activity 6.1: To identify the position of metals, non-metals and inert gases in the Periodic Table. (Page 139 of text book). 2. State five examples of the elements in the following table. Metal
Non-metal
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Inert gases
Metals and Non-metals 1. Compare the characteristics of metal and non-metal. Metals
Similarity
Non- metals
Metals
Characteristics Surface properties
Non-metals
Ductility Malleability Tensile strength Electrical conductivity Heat conductivity Melting point and boiling point Density
1. What are the uses of chlorine? __________________________________________________________________________________ 2. What are the uses of sulphur? __________________________________________________________________________________ 3. Why is copper suitable to be used to make electrical wire? __________________________________________________________________________________ 4. Why is aluminium used to make the plane? __________________________________________________________________________________ 5. Why is pot made of metal while its handle is made of non-metal materials such as plastic or wood? __________________________________________________________________________________
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Experiment 6.2: To study the characteristics of metal and non-metals Carry out experiment 6.2 (Page 172 of text book). Results: Physical characteristic Appearance Ductility Malleability Electrical conductivity Heat conductivity Melting point
Metal
Non-metal
Conclusion: Are the hypothesis? _____________________________________________________________________________________ _____________________________________________________________________________________ Questions: 1. What is the difference between the appearance of copper rod and carbon rod surface? ______________________________________________________________________________ 2. Between copper wire and pencil lead, which one can be bent? ______________________________________________________________________________ 3. Between iron and sulphur pieces, which one is malleable? ______________________________________________________________________________ 4. Which one can conduct electricity - iron, carbon or sulphur? ______________________________________________________________________________ 5. Between iron and carbon rod, which one can conduct heat? ______________________________________________________________________________ 6. Between tin and sulphur powder, which one has a higher melting point? ______________________________________________________________________________
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6.2 Mixtures 1. A mixture consists ___________ or __________ elements or compounds mixed _________________. 2. As the mixture is formed physically, it can be separated __________________ too.
Methods to separate mixtures. 1. List the methods to separate mixtures. (a)
(c)
Is the method used to separate an ____________solid from mixture of solid and liquid.
Is used to separate ________ solid mixtures in which one of the substances is ___________________ and the other is ________.
(b)
(d)
Is the method separate a completely _____________ liquid-liquid mixture that have different boiling points.
Is used to separate a liquid and ________________ solid mixture.
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(e)
(f)
Is used to separate____________ and ___________________ materials in water.
Is used to separate ___________ amount of mixture, for example separating the _____________ from the ink used.
Activity 6.4: To separate a mixture using filtration method Carry out activity 6.4 (Page 178 of text book). Questions: 1. What are the states of matter of sand and water? __________________________________________________________________________________ 2. Can the sand be separated physically from water? _________________________________________________________________________________ 3. Name the residue and filtrate in this activity. _________________________________________________________________________________ Activity 6.5: To separate a mixture using distillation method Carry out activity 6.5 (Page 179 of text book). Questions: 1. At what temperature does the liquid start to flow out of the condenser? _________________________________________________________________________________ 2. What is the use of porcelain chips in this experiment? _________________________________________________________________________________
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Activity 6.6: To separate a mixture using magnet Carry out activity 6.6 (Page 181 of text book). Questions: 1. Which powder will be attracted to the magnet? _________________________________________________________________________________ 2. Is the powder that you answered in question 1, a metal or non-metal? _________________________________________________________________________________
Activity 6.7: To separate a mixture using sedimentation method. Carry out activity 6.7 (Page 182 of text book). Questions: 1. Which substance is left inside the beaker? _________________________________________________________________________________ 2. Can water and sand be separated physically? _________________________________________________________________________________ Activity 6.8: To separate a mixture using floatation method. Carry out activity 6.8 (Page 183 of text book). Questions: 1. Between water and oil, which one floats? Why? _________________________________________________________________________________ 2. Can oil and water be separated physically? _________________________________________________________________________________
Activity 6.9: To separate a mixture using chromatography method. Carry out activity 6.9 (Page 184 of text book). Questions: 1. What are the colours produced on the filter paper? _________________________________________________________________________________ 2. Is the colour produced the same as the ink of the whiteboard marker pen? _________________________________________________________________________________
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6.3 Compounds 1. Compound – consists of ________or ________ elements that are mixed ____________________. 2. Components of a compound can only be separated ____________________. 3. _______________ and ________________ combine chemically to form compound. 4. A few types of compound formation are as following:
Metal + Oxygen
Metal oxide
Example: a) ________________+ oxygen
________________________
b) ________________ + oxygen
________________________
c) ________________ + oxygen
________________________
Metal + Water
Metal hydroxide hydroxide + hydrogen gas
Example: a) __________ + Water
_______________________ + ______________________
b) __________ + Water
_______________________ + ______________________
c) __________ + Water
_______________________ + ______________________
Metal + sulphur
Metal sulphide
Example: a) _____________ + Sulphur
________________________
b) _____________ + Sulphur
________________________
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Activity 6.7: To produce a compound. Carry out activity 6.11 (Page 186 of text book). Questions: 1. What is the colour of the mixture when it is heated? _________________________________________________________________________________ 2. Write the word equation of the chemical reaction that occurred? _________________________________________________________________________________ 3. What is the product of this reaction? _________________________________________________________________________________ 4. Is there any change in the mass of the compound before and after heating? _________________________________________________________________________________
Methods to Separate Compounds 1. A compound can only be separated by using chemical method which is through _________________ process. 2. Explain the meaning of electrolysis and draw a diagram of water electrolysis process.
Electrolysis is a______________________ ___________________________________ ___________________________________ ___________________________________
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Difference between Chemical Changes and Physical Changes State the similarity and differences of physical and chemical changes.
Differences between Mixtures and Compounds Complete the table below regarding the difference of mixtures and compounds.
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PT3 Practice 1. An iron nail and a nylon string is matter.
a) What will happen when the two substances above are heated? Give areason. ______________________________________________________________________________ ______________________________________________________________________________
b) (i) Aluminium metal is used to make drinking cans in a large scale.
Explain the characteristic of aluminium which enables it to be used for this purpose. ______________________________________________________________________________ ______________________________________________________________________________ (ii) The photo below shows the mining of bauxite to obtain aluminium. .
The source of aluminium is the Earth’s crust is limited. If aluminium is used in an uncontrolled way, it will eventually exhausted. Suggest ways to reduce the risk of using up the sources of aluminium in the Earth. ______________________________________________________________________________ ______________________________________________________________________________ 12
