Calcium sulfate is an inorganic compound with the chemical formula CaSO It is a white crystalline solid that occurs naturally in various forms including gypsum CaSO2HO and anhydrite CaSO Key Points Chemical Properties Calcium sulfate is a salt composed of calcium ions Ca and sulfate ions SO It is slightly soluble in water with solubility decreasing as the temperature increases Forms The most common form is gypsum which contains water in its crystal structure Anhydrite is the anhydrous form while hemihydrate CaSO05HO is used in products like plaster of Paris Applications Construction Widely used in the production of drywall cement and plaster Agriculture Serves as a soil conditioner and helps improve soil structure and drainage Food Industry Acts as a food additive E516 for firming and as a coagulant in products like tofu Medical Use Used in orthopedic casts due to its ability to harden when mixed with water Health and Safety Generally considered safe for use in food and construction however inhalation of dust can irritate the respiratory system Calcium sulfate plays a significant role in various industries due to its versatile properties and applications