Calcium hypochlorite is an inorganic compound with formula ₂. As a mixture with lime and calcium chloride, it is marketed as chlorine powder or bleach powder for water treatment and as a bleaching agent. This compound is relatively stable and has greater available chlorine than sodium hypochlorite (liquid bleach). It is a white solid, although commercial samples appear yellow. It strongly smells of chlorine, owing to its slow decomposition in moist air. It is not highly soluble in water and is more preferably used in soft to medium-hard water. It has two forms: dry and hydrated.