Question

What is a balanced chemical equation for the dissociation of solid magnesium hydroxide in water?

Answer 1

The balanced equation is Mg(OH)₂(s) ⇌ Mg²⁺(aq) + 2OH⁻(aq)

Magnesium hydroxide is sparingly soluble in water.

Only a small amount dissociates until the solution becomes saturated.

Then a dynamic equilibrium occurs in which Mg²⁺ and OH⁻ ions return to the surface of the solid as fast as they leave.