Predict the molar solubility of the following salt in a solution that contains the given concentration of one of its ions: BaSO₄; [SO₄^2-] = 4.3 × 10^-5 M; Ksp = 1.1 × 10^-10

Question

Quizplus · Accepted Answer

First, we need to write the equilibrium expression for the dissolution of BaSO4:
BaSO4(s) ⇌ Ba2+(aq) + SO42-(aq)

Given that [SO42-] = 4.3 × 10-5 M, we can use this to calculate the equilibrium concentration of Ba2+ using the Ksp expression:
Ksp = [Ba2+][SO42-] = 1.1 × 10-10
1.1 × 10-10 = [Ba2+](4.3 × 10-5)
[Ba2+] = 2.6 × 10-6 M

Since BaSO4 dissociates in a 1:1 ratio (1 Ba2+ ion per 1 BaSO4 molecule), the molar solubility of BaSO4 is equal to the equilibrium concentration of Ba2+:
molar solubility of BaSO4 = [Ba2+] = 2.6 × 10-6 M

Therefore, the correct answer is D (2.6 × 10-6 M).

Predict the Molar Solubility of the Following Salt in a Solution