Determine the molar solubility of CaSO₄ in a solution containing 0.100 M Na₂SO₄. K_sp (CaSO₄)= 2.4 × 10^-5. A)4.9 × 10^-3 M B)2.4 × 10^-4 M C)5.8 × 10^-10M D)1.2 × 10^-5 M E)0.10 M

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The balanced chemical equation for the dissolution of CaSO₄ in water is: CaSO₄(s) ⇆ Ca2+(aq) + S2-(aq) The equilibrium expression for the dissolution of CaSO₄ is: Ksp = [Ca2+][S2-] At equilibrium, the concentration of Ca2+ and S2- are equal to the molar solubility (s) of CaSO₄ in water. Therefore: Ksp = s^2 s = sqrt(Ksp) s = sqrt(2.4 × 10^-5) s = 4.9 × 10^-4 M However, the problem states that CaSO₄ is in a solution containing 0.100 M Na₂SO₄. This means that the concentration of S2- in solution is: [Na₂SO₄] = [S2-] Therefore, the equilibrium expression becomes: Ksp = [Ca2+][Na₂SO₄] At equilibrium, the concentration of Ca2+ is still equal to the molar solubility (s) of CaSO₄ in the solution containing Na₂SO₄. Therefore: Ksp = s[Na₂SO₄] s = Ksp/[Na₂SO₄] s = (2.4 × 10^-5)/(0.100) s = 2.4 × 10^-4 M Therefore, the molar solubility of CaSO₄ in a solution containing 0.100 M Na₂SO₄ is 2.4 × 10^-4 M, which is answer choice B.

Determine the Molar Solubility of CaSO4 in a Solution Containing

Determine the Molar Solubility of CaSO₄ in a Solution Containing