Question

A saturated solution of Mg(OH)2 is prepared having a large excess of Mg(OH)2. Sn(NO3)2 is added to the solution. Ksp = 1.9 x 10^-11 for Mg(OH)2 and Ksp = 6.0x10^-26 for Sn(OH)2.

What [Sn2+] is required so that the [Mg2+] in solution will be 0.15 M?

Answer 1

I would do this.
(Mg^+2)(OH^-)^2 = 1.9E-11
Plug in 0.15 for Mg and solve for (OH^-)^2.

Then (Sn^+2)(OH^-)^2 = 6.0E-26
Plug in (OH^-)^2 from above and solve for (Sn^+2)

Answer 2

Thanks, I got it right!