It is a salt of the hydrazinium cation N2H+5 and the azide anion N−3.

[1] The solid undergoes structural phase transition to a different crystalline arrangement at a pressure of 13 GPa.

[2] Hydrazinium azide decomposes explosively into hydrazine, ammonia, and nitrogen gas:[3] Crystallization with an equimolar amount hydrazine yields the solid hydrazinium azide hydrazinate, [N2H+5][N−3]·[N2H4], or N7H9, as monoclinic crystals.

This compound is less hygroscopic and less volatile than pure hydrazinium azide.

It decomposes explosively into nitrogen, hydrogen, and ammonia.