Question

What property of conc. H₂SO₄ is made use of in the following case? Give an equation for the reaction in this case:

Hydrogen chloride gas is passed through concentrated sulphuric acid.

Answer 1

Hydrogen chloride gas is dried by passing through concentrated sulphuric acid, as it does not react with concentrated sulphuric acid.

The conc. H₂SO₄ oxidises H₂S to SO₂.

\[\ce{H2SO4 + H2S -> 2H2O + S + SO2↑}\]