Calcite is a stable polymorph of calcium carbonate, which is the carbonic salt of calcium. It acts by neutralizing the hydrochloric acid found in gastric secretions. Calcite is often found in antacids. It is also commonly used as a food coloring agent and as a fertilizer. The molecular weight of calcium carbonate is 100.09 g/mol. It has a hydrogen bond donor count of zero, a rotatable bond count of zero, and a hydrogen bond acceptor count of three. Calcium carbonate has an exact and monoisotopic mass of 99.947335 g/mol. The heavy atom count of calcium carbonate is five. It also has a complexity of 18.8 and is a canonicalized compound. Calcium carbonate decomposes when boiled and has a melting point of 2,442°F (1,339°C). It is essentially insoluble in both water and alcohol. Calcium carbonate is commonly used for therapeutic purposes as a phosphate buffer during hemodialysis. It is also found in calcium supplements for the treatment and prevention of osteoporosis.