The acid-dissociation constant for benzoic acid (C6H5COOH) is 6.3×10−5. Calculate the equilibrium concentration of H3O+ in the solution if the initial concentration of C6H5COOH is 7.0×10−2 M .

Answer : The equilibrium concentration of in the solution is,

Explanation :

The dissociation of acid reaction is:

Initial conc.        c                                 0                0

At eqm.             c-x                                 x                x

Given:

c =

The expression of dissociation constant of acid is:

Now put all the given values in this expression, we get:

Thus, the equilibrium concentration of in the solution is,

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14,16 18 reacts with group