nitrous acid

Nitrous acid is an inorganic compound with the chemical formula HNO2. It is a weak and unstable acid, typically encountered only in solution or generated in situ due to its rapid decomposition into nitric oxide and nitric acid. Nitrous acid acts as a moderately strong oxidizing agent and is widely used in organic chemistry for diazotization reactions, particularly the preparation of diazonium salts from amines. These diazonium salts are key intermediates in the synthesis of azo dyes via azo coupling reactions and are also used in Sandmeyer reactions for aromatic substitution. In industry, nitrous acid is employed to neutralize toxic sodium azide and as an oxidizer in liquid fuel rockets. Medically, it has been used (as sodium nitrite) intravenously with sodium thiosulfate to treat acute cyanide poisoning by acting as an iron binder[1][2][3][4][5][8].

Other names

HNO2HNO-2HNO 2hydrogen nitrite