Q1. Heating sulphide ores in the presence of an excess of air is called:
A Calcination
B Roasting Correct
C Reduction
D Electrolysis
Explanation
Roasting is the process of heating sulphide ores strongly in the presence of excess air, usually to convert them into oxides and remove sulphur as sulphur dioxide. Calcination is heating ore in limited or no air and is commonly associated with carbonate ores. Reduction means removal of oxygen or gain of electrons, generally used after oxide formation in metallurgy. Electrolysis uses electric current to decompose or extract substances. The condition of excess air with sulphide ore identifies the process as roasting.