Calcium chloride on a watch glass. Calcium chloride anhydrous pellets; CaCl2; Molar mass 110.98??搶ol-1 Also known as Calcium II chloride, calcium dichloride, E509. It is an inorganic compound, a salt that is highly soluble in water. In its anhydrous form it is hygroscopic and used as a desiccant. As a food additive, E509, it is used as an acidity regulator, a sequestrant (a food additive which improves the quality and stability of foods) and it enhances the firmness in fruits and vegetables with a high average daily intake in western and other diets. There are no known harmful side effects.