Question

Heating an ore in the absence of air below its melting point is called:

• A. calcination
• B. smelting
• C. roasting
• D. leaching

Answer 1

Answer: (A)

Calcination: It is the process of heating the ore strongly in absence of air. The volatile impurities are removed and the mass becomes porous. Carbonate and oxide ores are generally calcined when they lose moisture, $\text{C}{\text{O}}_{\text{2}}$ and other volatile impurities. $\underset{\text{Malachite}}{\text{CuC}{\text{O}}_{\text{3}}\text{Cu(O}{\text{H}}_2\text{)}}\stackrel{\text{Calcination}}{\to }2CuO+C{O}_2$ $+H_{2}O$