How does the solubility of Mg(OH)2 in a buffered solution compare to the solubility of Mg(OH)2 in pure water?

Buffered at what pH. pH low the solubility is increased significantly. pH high, solubility is decreased significantly.

To determine how the solubility of Mg(OH)2 in a buffered solution compares to the solubility in pure water, we need to consider the effect of the buffer on the equilibrium between the solid Mg(OH)2 and its dissolved ions.

A buffer is a solution composed of a weak acid and its conjugate base (or a weak base and its conjugate acid) that helps maintain a constant pH. Buffers resist changes in pH when small amounts of acid or base are added to the solution.

When Mg(OH)2 is added to pure water, it dissolves partially due to the reaction:

Mg(OH)2 (s) ⇌ Mg2+ (aq) + 2 OH- (aq)

The solubility equilibrium is established, and the equilibrium expression is given by the solubility product constant (Ksp) expression:

Ksp = [Mg2+][OH-]^2

In a buffered solution, the presence of the buffer components introduces additional ions into the system. These additional ions can potentially affect the equilibrium by increasing or decreasing the solubility of Mg(OH)2.

The specific effect of the buffer on the solubility of Mg(OH)2 depends on the nature of the buffer. If the buffer contains ions that can react with the Mg2+ or OH- ions, it could lead to the formation of insoluble compounds, reducing the solubility of Mg(OH)2. On the other hand, if the buffer does not interfere with the solubility equilibrium, the solubility of Mg(OH)2 may remain similar to that in pure water.

To determine the exact effect of a specific buffer on the solubility of Mg(OH)2, you would need to consult its chemical composition and consider any potential reactions that could occur.

In conclusion, the solubility of Mg(OH)2 in a buffered solution can be influenced by the presence of the buffer components. The specific effect on solubility depends on the buffer's chemical composition and any potential reactions with Mg(OH)2.