A Ca(OH)2 solution has a pH of 8.0. [H3O+] = 1.0 x 10^-8 and [OH-] = 1.0 x 10^-6

Question

Determine [Ca(OH)2].

Answer 1

Ca(OH)2 WHAT? Ksp? perhaps?
........Ca(OH)2 ==> Ca^2+ + 2OH^-

Ksp = (Ca^2+)(OH^-)^2
(OH^-) = 1E-6 and (Ca&2+) = 1/2 that. Substitute into the Ksp expression and solve.