The molar solubility of a slightly soluble ionic compound M2X3 is 2.8 x 10-6 M. Determine the value of Ksp.

1.9 × 10⁻²⁶

Explanation:

Step 1: Write the solution reaction for M₂X₃

M₂X₃(s) ⇄ 2 M³⁺(aq) + 3 X²⁻(aq)

Step 2: Make an ICE chart

We can relate the molar solubility (S) with the solubility product constant (Ksp) using an ICE chart.

        M₂X₃(s) ⇄ 2 M³⁺(aq) + 3 X²⁻(aq)

I                              0               0

C                          +2S             +3S

E                            2S               3S

The solubility product constant is:

Ksp = [M³⁺]² × [X²⁻]³ = (2S)² × (3S)³ = 108 S⁵ = 108 (2.8 × 10⁻⁶)⁵ = 1.9 × 10⁻²⁶