more controlled way upon heating, releasing spectroscopically-pure gas. Solutions of hydrazoic acid dissolve many metals (e.g. zinc, iron) with liberation of hydrogen and formation of salts, which are called azides (formerly also called azoimides or hydrazoates). Hydrazoic acid may react with carbonyl derivatives, including aldehydes, ketones, and carboxylic acids, to give an amine or amide, with expulsion of nitrogen. This is called Schmidt reaction or Schmidt rearrangement. Dissolution in the strongest acids produces explosive salts containing the ion, for example: The ion is isoelectronic to diazomethane . The decomposition of hydrazoic acid, triggered by shock, friction, spark, etc. produces nitrogen and hydrogen: Hydrazoic acid undergoes unimolecular decomposition at sufficient energy: The lowest energy pathway produces NH in the triplet state, making it a spin-forbidden reaction. This is one of the few reactions whose rate has been determined for specific amounts of vibrational energy in the ground electronic state, by laser photodissociation studies. In addition, these unimolecular rates have been analyzed theoretically, and the experimental and calculated rates are in reasonable agreement. Toxicity Hydrazoic acid is volatile and highly toxic. It has a pungent smell and its vapor can cause violent headaches. The compound acts as a non-cumulative poison. Applications 2-Furonitrile, a pharmaceutical intermediate and potential artificial sweetening agent has been prepared in good yield by treating furfural with a mixture of hydrazoic acid () and perchloric acid () in the presence of magnesium perchlorate in the benzene solution at 35 °C. The all gas-phase iodine laser (AGIL) mixes gaseous hydrazoic acid with chlorine to produce excited nitrogen chloride, which is then used to cause iodine to lase; this avoids the liquid chemistry requirements of COIL lasers. References External links OSHA: Hydrazoic Acid Acids Azides Nitrogen hydrides Explosive chemicals Explosive gases Foul-smelling chemicals