Azide

In chemistry, azide (/ˈeɪzaɪd/, AY-zyd) is a linear, polyatomic anion with the formula N−3 and structure N=N=N. It is the conjugate base of hydrazoic acid HN3. Organic azides are organic compounds with the formula RN3, containing the azide functional group. The dominant application of azides is as a propellant in air bags. Sodium azide is made industrially by the reaction of nitrous oxide (N2O) with sodium amide (NaNH2) in liquid ammonia as solvent: Many inorganic azides can be prepared directly or indirectly from sodium azide. For example, lead azide, used in detonators, may be prepared from the metathesis reaction between lead nitrate and sodium azide. An alternative route is direct reaction of the metal with silver azide dissolved in liquid ammonia. Some azides are produced by treating the carbonate salts with hydrazoic acid. Azide has a linear structure and is isoelectronic with carbon dioxide (CO2), cyanate (OCN), nitrous oxide (N2O), nitronium ion (NO+2), molecular beryllium fluoride (BeF2) and cyanogen fluoride FCN. Per valence bond theory, azide can be described by several resonance structures; an important one being N=N=N.