The dissociation of weak electrolyte (a weak base or weak acid) is expressed in terms of
Channel: Doubtnut
Date: 02/08/2020

The dissociation of weak electrolyte (a weak base or weak acid) is expressed in terms of Ostwald's dilution law. An acid is substance which furnishes a proton or accepts an electron pair, where a base is proton acceptor or electron pair donor. Stronger is acid, weaker is its conjugate base. The dissociation constants of an acid `(K_(a))` and its conjugate base `(K_(b))` are related by `K_(w)=K_(a)xxK_(b)`, where `K_(w)` is ionic product of water equal to `10^(-14) at 25^(@)C`. The numerical value of `K_(w)` however increase with temperature. In a solution of an acid or base `[H^(+)][OH^(-)]=10^(-14)`. Thus the `[H^(+)]` in a solution is expressed as: `[H^(+)]=10^(-pH)` and `pH+pOH=14`. Buffer solution are the solutions which do not show appreciable change in the pH on addition of small amount of acid or base.    The pH of II gp. filtrate during III gp. basic radicals precipitation in qualitative anlysis is maintained by using a buffer solution of: