Hypochlorous Acid,

Hypochlorous Acid, $\backslash text\{HClO\}$, is the acid contained in bleaching powder. It can only be obtained as a dilute solution, as in the concentrated state it is very liable to decomposition. It is a powerful bleaching agent, and forms a series of salts, hypochlorites, which also possess bleaching properties. The chief of these are the hypochlorites of lime and soda. The lime salt is the important constituent of bleaching powder, while the soda salt is prepared commercially by passing chlorine into a solution of soda. For further information, see BLEACHING POWDER.—Hypo, in composition (Gr. 'under'), is used much like sub- from Latin. Hypochlorous acid has less oxygen than chlorous acid; hyposulphuric has less oxygen than sulphuric, but more than sulphurous acid. Hypophosphates are salts formed by hypophosphoric acid and a base.