Nitrite Salts

A salt of nitrous acid, containing the group NO2- is called a nitrite salt. Some examples of nitrite salts are ammonium nitrite, calcium nitrite, sodium nitrite, and potassium nitrate. Nitrites mainly decompose to N2 and NO. Nitrites may be further reduced to nitrogen by bacteria under some conditions. In blood, nitrite transforms hemoglobin to methemoglobin and is simultaneously oxidized to nitrate. Nitrite easily transforms into a nitrosating agent in an acidic environment and can react with a variety of compounds, e.g. ascorbic acid, amines, amides.

Nitrite salts are used in organic chemistry for N-nitrosation of amines. Nitrites are used in the food production industry as a food additive and preservative. Nitrites is also used in analytical and preparative chemistry, as corrosion inhibitors, and as an antidote in cyanide poisoning. Nitrites are the potential source of nitric oxide vasodilators. The nitrite ion is an ambidentate ligand and forms coordination complexes with metals. Nitrates are highly soluble and can be used as antifreeze. Cobalt complexes with varying colors containing the NO2 ligand find application in paints and dyes, and to color ceramics.