Hydroxides
dissociate when dissolved in water:
Ca(OH)2 -> Ca2+ + 2OH-
So there are 2 different particles. 1 mol of Ca(OH)2 produces 1 mol of Ca2+, and 2
moles of OH-.
Kps = [Ca2+] [OH-]^2
We will call “s” (solubility) the molarity of Ca(OH)2
So the molarity of Ca2+ is also “s” (same number)
And the molarity of OH- is “2s” (twice as much)
Kps = s*(2s)^2 = s*4s^2=4s^3
5.02 x 10-6 = 4s^3
(5.02 x 10-6)/4 = s^3
1.26 x 10-6 = s^3
s=cube root(1.26 x 10-6) = 0.0108M
