Sodium bromide  is a chemical compound that exists as a white crystalline solid at room temperature. The compound is inorganic, soluble in water, and has the molecular formula NaBr. Because sodium bromide is comprised of ionically bonded sodium atoms to bromine atoms, it is often used as a source of bromide ions. The compound is synthesized by combining  sodium hydroxide  (NaOH) with  hydrogen bromide  (HBr), where  HBr+NaOHH2O+NaBr���+����→�2�+���� . When combined, the salts of sodium bromide crystallize around 50.7° Celsius; without water, it crystallizes above that temperature, and with water, it crystallizes below this temperature.