Question

Consider the following statements. Roasting is carried out to:
(i) convert sulphide to oxide and sulphate.
(ii) remove impurities of CuS and FeS present in the ore of tin stone $\left(Sn{O}_2\right)$ as $CuS{O}_4$ and $FeS{O}_4$.
(iii) melt the ore.
(iv) remove arsenic and sulphur impurities.
Of these statements:

• A. (i), (ii) and (iii) are correct
• B. (ii), (iii) and (iv) are correct
• C. (i), (ii) and (iv) are correct
• D. (i), (ii), (iii),(iv) are correct

Answer 1

Answer: (C)

(i), (ii) and (iv) are correct

Roasting:- It is the process in which concentrated ore is heated to high temperatures in presence of excess of air. It is used for conversion of concentrated ore into its oxide.

This process is mainly used for sulphide ores to get the corresponding oxides, as the extraction of metal is easier from oxides.

Impurities like As and S are removed be roasting.

In the Sulphating roasting the sulphide ore is not converted into oxide but into soluble sulphate such as $CuS{O}_4$ and $FeS{O}_4$.

Option C is correct.