Lead Azide, Pb(N₃)₂

Lead Azide (Lead Azoimide, Lead Hydrazoate), Pb(N₃)₂, was prepared by Curtius by precipitating sodium or ammonium azoimide solution with lead acetate. It is soluble in excess of the precipitant, practically insoluble in cold water, but somewhat soluble in boiling water, a litre of which dissolves about 0.5 gram. It crystallises from aqueous solution in white needles which resemble lead chloride, but turn yellow in the light, and explode when heated. The salt dissolves in warm acetic acid, but not in ammonia. Hydrazoic acid is conveniently prepared by distillation when its lead salt is heated with dilute sulphuric acid.