Question

Why should the metal Sulphides and carbonates be converted to metal oxide in the extraction of minerals? Name the process involved in the conversion and write the equation for each process.

Answer 1

process of converting metal sulphides into metal oxides is called roasting
process of converting metal carbonates into metal oxides is called calcination

Answer 2

Hey Friend,

Actually, Sulphides and Carbonates are converted to their oxides because oxides are easy to reduce (reduction process of metal oxides is easier than reducing the sulphides and carbonates).

The conversion of sulphides and carbonates to their oxides is done by two processes - Roasting or Calcination.

1. For sulphide ores - Roasting
Roasting is the process in which the concentrated ore is heated in excess air.

2ZnS + 3O2 ---> 2ZnO + 2SO2
2FeS2 + 11O2 ---> 2Fe2O3 + 8SO2

2. For carbonate ores - Calcination
Calcination is the process in which the concentrated ore is heated in the absence of air.

ZnCO3 ---> ZnO + CO2
FeCO3 ---> FeO + CO2

Hope it helps!