Question

What is the molar solubility of $A{g}_{2}C{O}_3(K_{sp}=4\times {10}^{-13})$ in $0.1\text{M}N{a}_{2}C{O}_3$ solution?

• A. ${10}^{-6}$
• B. ${10}^{-7}$
• C. $2\times {10}^{-6}$
• D. $2\times {10}^{-7}$

Answer 1

The correct option is A ${10}^{-6}$

Let solubility of $A{g}_{2}C{O}_3$ in presence of $N{a}_{2}C{O}_3$ is $x$,
$A{g}_{2}C{O}_3\left(s\right)\rightleftharpoons 2A{g}^{+}(aq.)+C{O}_3^{2-}(aq.)$
$(x+0.1)\simeq 0.1$
$K_{sp}=\left[A{g}^{+}{]}^2\right[C{O}_3^{2-}]$
$\Rightarrow 4\times {10}^{-13}=(2x{)}^2\times 0.1$
$\Rightarrow x={10}^{-6}$