The solubility equilibrium for Fe(OH)2 is:
Fe(OH)2 (aq) ↔ Fe²⁺ (aq) + 2OH⁻ (aq)
Ksp(Fe(OH)2) = [Fe²⁺][OH⁻]²
If 's' is the molar solubility of Fe(OH)2 then:
Ksp = (s)(2s)² = 4s³
the solubility constant Ksp for Fe(OH)2 can be obtained from any online database= 4.87*10⁻¹⁷
4.87*10⁻¹⁷ = 4s³
s³ = 1.218*10⁻¹⁷
s = ∛1.218*10⁻¹⁷ = 2.33*10⁻⁶ M
Molar solubility of Fe(OH)2 = 2.33*10⁻⁶ M
