Question

What is the $H^{+}$ ion concentration of $5\times {10}^{-3}M{H}_2{CO}_3$ solution having $10$% dissociation :-

• A. ${10}^{-3}$
• B. ${10}^{-2}$
• C. ${10}^{-1}$
• D. $5X{10}^{-2}$

Answer 1

The correct option is A ${10}^{-3}$

$H_{2}C{O}_3\rightleftharpoons 2H^{+}+C{O}_3^{2-}$

If $H_{2}C{O}_3$ is dissociated by $100$%, then $5\times {10}^{-3}M$ $H_{2}C{O}_3$ will give $10\times {10}^{-3}M$ of $H^{+}$.

Now as it is having $10$% dissociation, so concentration of $H^{+}$ ion=$\frac{10\times {10}^{-3}}{10}={10}^{-3}$

Hence, option $A$ is correct.