Hypochlorous acid, dissociation constants

In addition to influencing the rate of a reaction, pH may also control the products where alternate or sequential pH-dependent reactions take place. An example of this type of reaction is the chlorination of phenol. Lee and Morris (37) have shown that the chlorination of phenol proceeds by the stepwise substitution at the 2, 4, and 6 positions of the aromatic ring. The rate of each of these reactions depends on the product of phenate or chlorophenate anion and the hypochlorous acid concentrations. Since each phenolic compound has a slightly different acid dissociation constant, the species of chlorophenols that are formed depend on the pH of the solution. 

Remark A <,(HC10, CIO ) is the acid dissociation constant of hypochlorous acid ... 

Hypochlorous acid is a weak acid with a dissociation constant equal to 3 to 4 x 10 8, which is about 1/600th the strength of acetic acid. When it is stored it slowly decomposes according to the following equations ... 

Can carbonic acid displace hypochlorous acid from a solution of its salt Compare the values of the dissociation constants of carbonic and hypochlorous acids (see Appendix 1, Table 9). 

Diphosphothymidine, I, 242 Diplococcua pneumoniae, polysaccharides formed by, II, 221 Disaocharides, III, 130 enzymatic syntheses of, V, 29-48 oxidation of, III, 132, 145 Dismutation, the term, IV, 101 Disproportionation, IV, 102 Dissociation constants, of hypobromous, hypochlorous and hypoiodous acids,... 

The hypohalous acids are very weak and their salts may be decomposed by carbon dioxide. The respective dissociation constants of hypochlorous acid, hypobromous acid and hypoiodous acid are 6.5 X 10 , 2.0 X and 5 X 10" . The values listed are representative ones the data in the literature vary from 3.2 to 10.5 X 10" for hypochlorous acid, and the value for hypoiodous acid is only an estimate. 

Since the dissociation constant for hypochlorous acid is very small, in neutral solutions undissociated hypochlorous acid is the dominant species of this equilibrium (Eq. 5.3). 

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