What is the balanced chemical equation that describes the dissociation of the strong base magnesium hydroxide, Mg(OH)2 in water?

1 Answer
Ernest Z.
Jul 14, 2014

The equation is Mg(OH)2(s)⇌Mg2+(aq)+2OH-(aq).

Explanation:

Mg(OH)2 is a strong base.

Mg is a Group 2 Metal, so it form Mg2+ ions. Each ion pairs up with two OH- ions to form the neutral compound, Mg(OH)2.

Magnesium hydroxide is "insoluble", so only a small amount it goes into solution. But every bit that goes into solution dissociates into Mg2+ ions and OH- ions.

There is a dynamic equilibrium between the solid compound and the ions in solution.

Mg(OH)2(s)⇌Mg2+(aq)+2OH-(aq)

The Mg2+ ions and the OH- ions are leaving the surface of the solid at the same rate as they return from the solution to the surface of the solid.

Here's a video showing the process.

Related questions
See all questions in Stoichiometry with Acid and Base Dissociation
Impact of this question
88046 views around the world
You can reuse this answer
Creative Commons License