Question

The correct relation between $K_{(}sp)$ and solubility for the salt K AI$({SO}_4{)}_2$ is:

• A. ${4s}^4$
• B. ${27s}^4$
• C. ${108s}^5$
• D. None of these

Answer 1

The correct option is A ${4s}^4$

$\underset{\text{At equillibrium}:}{\underset{\text{Initial}:}{}}\underset{-}{\underset{-}{KAl{\left(S{O}_4\right)}_2}}⟶\underset{s}{\underset{-}{K^{+}}}+\underset{s}{\underset{-}{{Al}^{+3}}}+\underset{2s}{\underset{-}{2{S{O}_4}^{-2}}}$

For the above reaction,

$K_{sp}=\left[K^{+}\right]\left[{Al}^{+3}\right]{\left[{S{O}_4}^{-2}\right]}^2$

$\Rightarrow K_{sp}=\left(s\right)\left(s\right){\left(2s\right)}^2=4s^4$

Hence, the relation between $K_{sp}$ and solubility for the salt $KAI{\left(S{O}_4\right)}_2$ is $4s^4$.