Answer
is: molar solubility of iron(II) hydroxide is 2,3·10⁻⁶ M.
Chemical reaction: Fe(OH)₂(s) → Fe²⁺(aq) + 2OH⁻(aq).
s(Fe(OH)₂) = ?M.
s(Fe(OH)₂) =
s(Fe²⁺) = x.
s(OH⁻) =
2s(Fe(OH)₂) = 2x.
Ksp = s(Fe²⁺) ·
(s(OH⁻))².
Ksp = x · (2x)².
4,87·10⁻¹⁷ = 4x³.
x = ∛(4,87·10⁻¹⁷ ÷ 4).
x = 2,3·10⁻⁶ M.
