Question

Calculate the solubility (in m) of cobalt(ii) hydroxide, co(oh)2(s) in h2o. ksp = 1.00×10-16 at a specific temperature.

Answer 1

according to this reaction:

by using the ICE table:

CO(OH)2 → CO2+ + 2OH-

intial 0 0

change +X +2X

Equ X 2X

when Ksp = [CO2][OH-]^2

by substitution:

3.6 x 10^-16 = X * (2X)^2

3.6 x 10^-16 = 4 X^3

∴X = 3.88 x 10^-6 M