Question

Choose the correct option using the code regarding roasting process.
(I) It is the process of heating the ore in air in a reverberatory furnace to obtain the oxide.
(II) It is an exothermic process.
(III) It is used for the concentration of sulphide ore.
(IV) It removes easily oxidisable volatile impurities present in the concentrated ore.

• A. I, II and III
• B. I, II and IV
• C. I, III and IV
• D. I, II, III and IV

Answer 1

Answer: (D)

Ore is heated below its melting point in a reverberatory furnace in the presence of air to convert it into its oxides. It removes easily oxidisable volatile impurities like arsenic as $A{s}_2{O}_3$, antimony as $S{b}_2{O}_3$ and sulphur as $S{O}_2$. Roasting is an exothermic process; once started it does not require additional heating.