Question

Which of the following process does not involve calcination?

Options

• \[\ce{CaCO3 -> CaO + CO2}\]

• \[\ce{2FeS + 3O2 -> Fe2O3 + 2SO2}\]

• \[\ce{Fe2O3 * 3H2O -> Fe2O3 + 3H2O}\]

• \[\ce{CuCO3 * Cu(OH)2 -> 2CuO + H2O + CO2}\]

Answer 1

\[\ce{\mathbf{2FeS + 3O_2 \leftarrow Fe_2O_3 + 2SO_2}}\]

Explanation:

Calcination is the process of heating a concentrated ore in limited supply of air below its melting point, typically used to decompose carbonates into oxides or remove water of crystallization from hydrated oxides. \[\ce{2FeS + 3O2 -> Fe2O3 + 2SO2}\] is a roasting process for sulphide ore, where (FeS) is oxidized to (Fe₂O₃) and (SO₂) gas is released, and does not involve calcination.