Hypohalous Acids, HOX, and Hypohalites, OX

Hypochlorous acid is readily made by the general reaction of Equation (18.31), particularly if conducted at low temperatures to limit the rate of the disproportionation reaction. Equation (18.33). Industrially, HOCl is prepared by the gaseous hydrolysis of dichlorine oxide, CI2O, shown in Equation (18.34)  

Hypochlorites made thisway are used in huge quantities as bleaches. (See Section 18.5 under Bleaches for further details on the mechanism of bleaching.) 

Hypochlorite salts are among the best and most widely used oxidizing agents. Their reactions with a variety of atoms and ions usually result in the net transfer of one or more oxygen atoms to the reactant. Some common examples are given in Equations (18.35) through (18.37)  

The moderately high rate of the disproportionation of hypobromite makes it difficult to store and therefore of little use as an oxidizing agent. The rate is so high for hypoiodite that it is virtually unknown in aqueous solution. 

Chlorous acid is the only one of the possible three halous acids that exists beyond a shadow of doubt. It is a much stronger acid than hypochlorous (by six orders of magnitude) but is stiU classified as a weak acid. It cannot be isolated in the free 

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