Equilibrium Question 274
Question: A precipitate of $ CaF_2(K _{sp}=1.7\times {10^{-10}}) $ will be obtained when equal volume of the following are mixed [MP PMT 1990, 95; IIT 1982; MNR 1992]
Options:
A) $ {10^{-4}}M,C{a^{2+}} $ and $ {10^{-4}}M,{F^{-}} $
B) $ {10^{-2}}M,C{a^{2+}} $ and $ {10^{-3}}M,{F^{-}} $
C) $ {10^{-5}}M,C{a^{2+}} $ and $ {10^{-4}}M,{F^{-}} $
D) $ {10^{-3}}M,C{a^{2+}} $ and $ {10^{-4}}M,{F^{-}} $
Show Answer
Answer:
Correct Answer: B
Solution:
$ [C{a^{2+}}]{{[{F^{-}}]}^{2}}=[ \frac{{10^{-2}}\times V}{2V} ]\times {{[ \frac{{10^{-3}}\times V}{2V} ]}^{2}} $
$ =1.25\times {10^{-9}} $ .
