odium hypochloriteÃÂ is aÃÂ chemical compoundÃÂ with theÃÂ formulaÃÂ NaOCl or NaClO, comprising aÃÂ sodiumÃÂ cationÃÂ (+
) and aÃÂ hypochloriteÃÂ anionÃÂ (ÃÂ¢ÃÂÃÂ
). It may also be viewed as the sodiumÃÂ saltÃÂ ofÃÂ hypochlorous acid. The anhydrous compound is unstable and may decompose explosively.ÃÂ It can be crystallized as aÃÂ pentahydrateÃÂ
2O, a pale greenish-yellow solid which is not explosive and is stable if kept refrigerated.
Sodium hypochlorite is most often encountered as a pale greenish-yellow dilute solution commonly known asÃÂ liquid bleachÃÂ or simplyÃÂ bleach, aÃÂ household chemicalÃÂ widely used (since the 18th century) as aÃÂ disinfectantÃÂ or aÃÂ bleaching agent. The compound in solution is unstable and easily decomposes, liberatingÃÂ chlorine, which is the active principle of such products. Indeed, sodium hypochlorite is the oldest and still most importantÃÂ chlorine-based bleach.
Its corrosive properties, common availability, and reaction products make it a significant safety risk. In particular, mixing liquid bleach with other cleaning products, such as acids orÃÂ ammonia, may produce toxic fumes.