Hypochlorous, hy puh KLAWR uhs, acid is a weak, inorganic acid that forms when chlorine is added to water. It is unstable and decomposes rapidly when exposed to heat or light. Hypochlorous acid is used as a household bleach and disinfectant. Chemists believe that when chlorine is added to swimming pools and city water supplies, it is the hypochlorous acid that forms which kills the bacteria. Neutralizing hypochlorous acid produces salts called hypochlorites. Both the acid and its salts are powerful oxidizing agents.