molar solubility?

Question

The Ksp for Mg(OH)2 = 5.6 x 10^-12. What is the molar solubility of Mg(OH)2 in a buffer solution of pH 10.85?

Answer 1

1. work out [H+] at pH 10.85
2. work out [OH-] at this pH
3. take the square root of [OH-]
4. divide by Ksp for your answer