Barium azide [Ba(N3)2] on heating gives Ba and N2. This reaction is a source of pure nitrogen. Ba(N3)2‌
Δ
→
‌Ba+3N2 Ammonium chloride on reaction with calcium hydroxide gives nitrogen as follows NH4‌Cl+NaNO2→N2+2H2O+NaCl Both reactions are used for preparation of nitrogen.
