The element compound of hydrochloric acid is hydrogen chloride (HCl). Hydrogen chloride is a colorless gas with a pungent odor. It is highly soluble in water, forming hydrochloric acid. Hydrogen chloride is produced by the reaction of hydrogen gas and chlorine gas. It is also produced by the reaction of sodium chloride and sulfuric acid. Hydrogen chloride is used in the production of a variety of chemicals, including polyvinyl chloride (PVC), hydrochloric acid, and chlorinated solvents.