The solubility of manganese (II) hydroxide (Mn(OH)₂) is 2.2 × 10^-⁵M. What is the Ksp of Mn (OH)₂? A) 4.8 × 10^-¹⁰ B) 2.2 × 10^-⁵ C) 2.1 × 10^-¹⁴ D) 4.3 × 10^-¹⁴ E) 1.1 × 10^-¹⁴

Question

Quizplus · Accepted Answer

The solubility product constant (Ksp) for a slightly soluble compound is the product of the concentration of the ions in solution when the compound is in equilibrium with the solid.

The balanced chemical equation for the dissolution of manganese (II) hydroxide is:

Mn(OH)2(s) ⇌ Mn2+(aq) + 2OH-(aq)

The solubility of Mn(OH)2 is 2.2 × 10^-15 mol/L, which means that [Mn2+] = 2.2 × 10^-15 mol/L and [OH^-] = (2 x 2.2 × 10^-15) mol/L = 4.4 × 10^-15 mol/L at equilibrium.

Therefore, the Ksp for Mn(OH)2 is:

Ksp = [Mn2+][OH^-]^2 = (2.2 × 10^-15 mol/L)(4.4 × 10^-15 mol/L)^2 = 4.3 × 10^-25

The answer choice that matches this calculation is D.

The Solubility of Manganese (II) Hydroxide (Mn(OH)2) Is 2

The Solubility of Manganese (II) Hydroxide (Mn(OH)₂) Is 2