Determine the molar solubility of CuCl in a solution containing 0.020 M LiCl. K_sp (CuCl)= 1.0 × 10^-6. A) 1.0 × 10^-12 M B) 2.0 × 10^-8 M C) 5.0 × 10^-5 M D) 1.0 × 10^-3 M E) 0.20 M

Question

Quizplus · Accepted Answer

The solubility of CuCl in pure water can be calculated using its equilibrium constant:
CuCl (s) ⇌ Cu+ (aq) + Cl- (aq)
K = [Cu+][Cl-]/[CuCl] = 1.0 × 10-6
Let the molar solubility of CuCl in the presence of 0.020 M LiCl be x. Then, the equilibrium expression for its dissolution becomes:
CuCl (s) + Li+ (aq) ⇌ Cu+ (aq) + LiCl (s)
The equilibrium constant expression is:
K = [Cu+][LiCl]/[CuCl][Li+] = (x)(0.020)/(x)(0.020) = x2/0.020
Substituting K and solving for x:
x2 = K × 0.020 = (1.0 × 10-6)(0.020) = 2.0 × 10-8
x = √(2.0 × 10-8) = 4.5 × 10-5 M
Therefore, the molar solubility of CuCl in a solution containing 0.020 M LiCl is 4.5 × 10-5 M, which is closest to choice C (5.0 × 10-5 M).

Determine the Molar Solubility of CuCl in a Solution Containing