Equilibrium Question 214
Question: If the concentration of lead iodide in its saturated solution at $ 25^{o}C $ be $ 2\times {10^{-3}} $ moles per litre, then its solubility product is [CPMT 1984]
Options:
A) $ 4\times {10^{-6}} $
B) $ 8\times {10^{-12}} $
C) $ 6\times {10^{-9}} $
D) $ 32\times {10^{-9}} $
Show Answer
Answer:
Correct Answer: D
Solution:
$ \underset{K _{sp}}{\mathop{PbI_2}}, $ ⇌ $ \underset{S}{\mathop{P{b^{++}}}},+\underset{2S,}{\mathop{2{I^{-}}}}, $
$ K _{sp}=4S^{3}=4\times {{[2\times {10^{-3}}]}^{3}} $
$ =32\times {10^{-9}} $ .
