Question

The solubility product $\left(K_{ sp }\right)$ of $AgCl$ is $1.8 \times 10^{-10}$. Precipitation of $AgCl$ will occur only when equal volumes of solutions of

• A. $10^{-4}\, M \,Ag ^{+}$and $10^{-4} M \,Cl ^{-}$are mixed
• B. $10^{-7}\, M \,Ag ^{+}$and $10^{-7} M \,Cl ^{-}$are mixed
• C. $10^{-5}\, M\, Ag ^{+}$and $10^{-5} M \,Cl ^{-}$are mixed
• D. $10^{-10} \,M \,Ag ^{+}$and $10^{-10} M \,Cl ^{-}$are mixed

Answer 1

Answer: (A)

Precipitation of $AgCl$ will occur only when ionic product is greater than solubility product.
This is possible only in case, when $10^{-4} M Ag ^{+}$and $10^{-4} M Cl ^{-}$are mixed,
i.e. ionic product $=10^{-4} \times 10^{-4}=10^{-8}$