Chemical And Ionic Equilibrium Result Question 31

31. The precipitate of $\mathrm{CaF}2,\left(K{\mathrm{sp}}=1.7 \times 10^{-10}\right)$ is obtained, when equal volumes of which of the following are mixed?

(1982, 1M)

(a) $10^{-4} \mathrm{M} \mathrm{Ca}^{2+}+10^{-4} \mathrm{M} \mathrm{F}^{-}$

(b) $10^{-2} \mathrm{M} \mathrm{Ca}^{2+}+10^{-3} \mathrm{M} \mathrm{F}^{-}$

(c) $10^{-5} \mathrm{M} \mathrm{Ca}^{2+}+10^{-3} \mathrm{M} \mathrm{F}^{-}$

(d) $10^{-3} \mathrm{M} \mathrm{Ca}^{2+}+10^{-5} \mathrm{M} \mathrm{F}^{-}$