First slide

Ionization constants of weak acids, PH of weak acids

Question

For the ionization of ortho phosphoric acid
$\large {H_3}P{O_4}\, \rightleftharpoons \,{H_2}P{O_4}^ - \, + \,{H^ + }({K_1})$
${H_2}P{O_{4}^{-}}\, \rightleftharpoons \,HP{O_{4}^{-2}}\, + \,{H^ + }({K_2})$
$\large HP{O_{4}^{-2}}\, \rightleftharpoons \,P{O_{4}^{-3}}\, + \,{H^ + }({K_3})$
, $K_{1}, K_{2}, K_{3}$ are successive ionization constants of the acid. Correct relation is

Easy

A

K₁ > K₂ > K₃
B

K₁ < K₂ < K₃
C

K₁< K₂ > K₃
D

K₁.K₂.K₃ = K_w

Solution

$\large {H_3}P{O_4}\, \rightleftharpoons \,{H_2}P{O_4}^ - \, + \,{H^ + }$           $\large {K_{{a_1}}}$ $\large ={7}\times 10^{-3}$
   $\large {K_{{a_2}}}$ $\large ={6}\times 10^{-8}$
         $\large {K_{{a_3}}}$ $\large ={5}\times 10^{-13}$
For a polyprotic acid the successive dissociation constants decreases.

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App