Question

Name the gas evolved in following case:
The gas produced by the action of concentrated sulphuric acid on sodium chloride.

Answer 1

Hydrochloric gas is produced when concentrated sulphuric acid reacts with sodium chloride. The chemical reaction at temperature below 200⁰C is as follows:
${\text{NaCl + H}}_{2}S{O}_4\stackrel{{\text{<200}}^{0}C}{\to }{\text{NaHSO}}_4+\text{HCl}$