<unk>  (commonly known in a dilute solution as bleach) is a chemical compound with the formula<unk>  or<unk> , comprising a sodium cation () and a<unk>  anion (or ). It may also be viewed as the sodium salt of hypochlorous acid. The anhydrous compound is unstable and may decompose explosively. It can be crystallized as a pentahydrate ·5, a pale greenish-yellow solid which is not explosive and is stable if kept refrigerated.<unk>  is most often encountered as a pale greenish-yellow dilute solution referred to as liquid bleach, which is a household chemical widely used (since the 18th century) as a disinfectant or a bleaching agent. In solution, the compound is unstable and easily decomposes, liberating chlorine, which is the active principle of such products.<unk>  is the oldest and still most important 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 found in limescale-removing products, will produce chlorine gas, which was used as a poison gas in World War I. A common urban legend states that mixing bleach with ammonia also releases chlorine, but in reality the two chemicals react differently, producing chloramines and/or nitrogen trichloride. With excess ammonia and sodium hydroxide, hydrazine may be generated.
Sodium hypochlorite
Amylmetacresol
Sodium hydroxide
Povidone-iodine
Tetrachlorodecaoxide
Chloroethane
Denatured alcohol
Silver nitrate