Question

The process in which the ore is heated in excess of air below its melting point is known as ______.

Answer 1

The process in which the ore is heated in excess of air below its melting point is known as roasting.

Explanation:

Roasting is a metallurgical process primarily used for sulphide ores, where the concentrated ore is heated to high temperatures in a continuous, excess supply of air. This thermal treatment converts metal sulphides into their corresponding metal oxides while expelling volatile impurities such as sulphur, arsenic, and phosphorus as gases. For example, heating zinc blende (ZnS) in air converts it into zinc oxide (ZnO) and releases sulphur dioxide gas (SO₂).