(viii) Which element is oxidised in the following reaction?

2FeSO₄ +CI₂ +H₂SO₄ → Fe(SO₄)₃+ 2HCl.

1. Chlorine
2. Hydrogen
3. Oxygen
4. Sulphur
5. Iron

Aluminium does not react with water and does not corrode much in air because

1. it is below hydrogen in the reactivity series
2. it forms a stable carbonate which prevents reactions
3. the metal is covered with a protective coating of an oxide
4. aluminium ions have positive charges
5. it is very stable.

What will happen when zinc is placed in aqueous copper (II) sulphate?

1. Copper atoms are oxidized
2. Zinc atoms are oxidized
3. Copper ions are oxidized
4. Zinc ions are oxidized
5. Sulphur atoms are oxidized.

Copper can be separated from a mixture of zinc and copper by adding to the mixture

1.  concentrated H2SO ₄
2.  dilute H2SO 4
3.  aqueous solution of ZnSO4
4.  concentrated HNO₃
5.  a catalyst.

Which carbonate is the most stable to heat?

1. Calcium carbonate
2. Copper (II) carbonate
3. Lead (II) carbonate
4. Zinc carbonate
5. .Iron (II) carbonate.

11. An unknown green sample was mixed with dilute HNO₃ and gave a blue solution and a gas which precipitated lime water. The resulting solution was evaporated to dryness and upon further heating black residues was formed together with a brown gas which relighted a glowing splint.

(a) Identify the green sample, blue solution, the black solid and the two gases.

(b) Give balanced chemical equation for the reaction between the green sample and nitric acid, and the equation for the formation of black residues.

A Form Three student conducted experiments in the laboratory to synthesize nitrogen, ammonia and ethane. The experimental results were tabulated as follows:

Write word equations with corresponding chemical equations to summarize the reactions taking place in each of the experiments I to 3.

Carbon dioxide can be prepared by adding an acid to calcium carbonate.

(i) Using a named acid, write a balanced chemical equation for the reaction.

(ii) Name all the products formed in (i).

A student investigated different reactivity of a set of metals by placing pieces of each metal in metal nitrate solution. Table 2 shows some of the results.

Table: 2.

Where: _{ } = reaction observed and X = no reaction.

1. Use the most results given to arrange the metals in order of reactivity starting with the most reactive metal.

2. Use the reactivity series in 11 (b) (i) to complete Table 2.

  Match the items in List A which the responses in List B by writing the letter of the correct response beside the item number in the answer booklet provided.

 With the aid of chemical equations, explain what will happen when aluminium chloride reacts with water.

 A student accidently broke a beaker containing copper (II) sulphate crystals. He decided to separate the blue crystals from the small pieces of glass by first dissolving the mixture and then filtering. What were his next steps?

(i) State the difference between physical strength and chemical strength of metals.

(ii) Giving example, explain why preparation of metallic oxides by direct method is not intensively used.