Ageneric salt, ab3, has a molar mass of 203 g/mol and a solubility of 8.30 g/l at 25 °c. what is the ksp of this salt at 25 °c?

7.56 × 10⁻⁵

Explanation:

Let's consider the solution of the poorly soluble salt AB₃.

AB₃(s) ⇄ A³⁺(aq) + 3 B⁻(aq)

The molar solubility of the salt (S) is:

In order to relate S to the solubility product (Ksp), we will use an ICE Chart.

     AB₃(s) ⇄ A³⁺(aq) + 3 B⁻(aq)

I                     0               0

C                   +S            +3S

E                    S               3S

The solubility product is:

Ksp = [A³⁺].[B⁻]³ = S . (3S)³ = 27 S⁴ = 27 (0.0409)⁴ = 7.56 × 10⁻⁵