Question

When nitrogen can be formed directly by decomposition of ammonium nitrite, why we start with ammonia chloride in laboratory?

Answer 1

To prepare pure nitrogen in the laboratory, a mixture of ammonium chloride ($N{H}_{4}Cl$) and sodium nitrite ($NaN{O}_2$) is heated. The first product that is formed is ammonium nitrite ($N{H}_{4}N{O}_2$). This compound is very unstable, and breaks up into nitrogen and water. Caution must be used in this experiment to avoid explosive reactions.