Question

At ${30}^{o}C$, the solubility of $A{g}_{2}C{O}_3(K_{sp}=8\times {10}^{-12})$ would be maximum in 1 litre of:

• A. $0.05MN{a}_{2}C{O}_3$
• B. $0.05MAgN{O}_3$
• C. Pure water
• D. $0.05MN{H}_3$

Answer 1

The correct option is B $0.05MAgN{O}_3$

$Inpurewater$

$A{g}_{2}C{O}_3\leftrightharpoons 2A{g}^{+}+C{O}_3^{2-}$

$InN{H}_3$

$A{g}_{2}C{O}_3\leftrightharpoons 2A{g}^{+}+C{O}_3^{2-}$

$2A{g}^{+}+4N{H}_3\leftrightarrow 2Ag(N{H}_3{)}_2^{+}$

$Overall:A{g}_{2}C{O}_3+4N{H}_3\leftrightarrow 2Ag(N{H}_3{)}_2^{+}+C{O}_3^{2-}$

Here a complex formation is taking place, due to the formation of complex the reaction between silver ion's and ammonia shift the solubility equilibria in the forward direction which in turns increases the solubility.

$AgN{O}_3$ and $N{a}_{2}C{O}_3$ : Due to the presence of common ions in these reactions the solubility is supressed.

Therefore, $A{g}_{2}C{O}_3$ will be most soluble in $N{H}_3$.