Question

The concentration of Mg2+ ion in a solution is 0.010M. At what pH will Mg(OH)2 first precipitate? (Given Ksp Mg(OH)2 equals 1.2*10-11)

Answer 1

........Mg(OH)2 ==> Mg^2+ + 2OH^-
Ksp = (Mg^2+)(OH^-)^2
Plug in 0.01 M for (Mg^2+) and solve for OH-, then convert OH^- to pH.

Answer 2

thanks I understand now