Equilibrium Question 150
Question: If the solubility product $ K _{sp} $ of a sparingly soluble salt $ MX_2 $ at $ 25{}^\circ C $ is $ 1.0\times {10^{-11}} $ , the solubility of the salt in mole litre-1 at this temperature will be [RPMT 2000]
Options:
A) $ 2.46\times 10^{14} $
B) $ 1.36\times {10^{-4}} $
C) $ 2.60\times {10^{-7}} $
D) $ 1.20\times {10^{-10}} $
Show Answer
Answer:
Correct Answer: B
Solution:
$ MX_2 $ ⇌ $ \underset{(S),}{\mathop{{M^{+}}}},+\underset{{{(2S)}^{2}}}{\mathop{2{X^{-}}}}, $ ; $ K _{sp}=4S^{3} $
$ S=\sqrt[3]{\frac{K _{sp}}{4}}=\sqrt[3]{\frac{1\times {10^{-11}}}{4}}=1.35\times {10^{-4}} $
