What is the solubility of Mg(OH)2 in a solution buffered at pH 8.80.
The Attempt at a Solution
The answer is .45 M or 26 g/L but I can't get that for some reason.
I can find the concentration of hydroxide [OH-] = 6.3 x 10-6
Mg(OH)2 -> Mg+2 + 2OH-
................0+x,....6.3x10-6 + 2x
1.8x10-11 = x(6.3x10-6 + 2x)^2
x = 1.65 x 10-4 M (neglecting the 6.3 x10-6)
I've also tried solving the cubic with similar results.
Does anyone where I went wrong?