Sodium Metabisulphite is a white/creamy chemical which is soluble in water. Its chemical formula is Na2S2O5, an inorganic compound made up of sodium, sulphur and oxygen, and used in many industries such as food, textile, mining, water treatment, construction chemicals and paper. Sodium metabisulfite is a white, granular solid. It is used in the pulp and paper industry, in the photographic industry and in the various other industries as a bleach or dechlorinator. Food Grade sodium metabisulfite may be used as a food preservative. Sodium metabisulfite can also be used in the manufacture of other chemicals.