Question

Q. (a) An ore, on heating in air, gives Sulphur Dioxide gas. Name the method in each metallurgical step, that will be required to extract this metal from its ore.
(b) State which of the following reactions will take place or not, giving suitable reason for each:-
Zn(s) + CuSO4(aq)------------> ZnSO4 (aq) + Cu (s)
Fe (s) + ZnSO4(aq)-------------> FeSO4 (aq) + Zn (s)

Answer 1

a. An ore on heating gives SO₂ in air means the ore is sulphide ore. The process involved in the extraction of metal from sulphide ores are
1. The sulphide ore is concentrated by froth floatation method to remove impurities
2. The concentrated ore is roasted in the presence of air to convert to metal oxide with the liberation of sulphur dioxide.
3. Reduction of metal oxide to metal using carbon
4. The metal is purified by electrolytic reduction.

b. As Zn is more reactive than copper it displaces copper from copper sulphate solution. So first reaction is possible.
In the second reaction iron is less reactive than zinc , it does not displace zinc from zinc sulphate solution.