According to the reaction equation:
CaF2(s) ⇄ Ca2+(aq) + 2F-(aq)
So the Q expression will be = [Ca2+][F-]^2
and we will neglect the [ CaF2] as it is solid
so, by substitution:
when we have [Ca2+] = 0.01
and [F-] = 0.015
Q = 0.01 * (0.015)^2
= 6.3 x 10^-2
by comparing Q value which is 6.3 x 10^-2 and Ksp value which is 1.8 x 10^-5
So, we can see that Q > Ksp
-that means precipitation will form as ion concentration are greater than
equilibrium concentration So, the reaction will proceed in reverse to achieve
equilibrium . and the solution will be then supersaturated.
