What are the concentrations of Cu+1(aq) and Cl-1(aq) ions in the saturated solution?

Question

You prepared a saturated solution of copper(I) chloride (Ksp = 1.248x10^-6), but this time instead of using pure water as the solvent, you use a 0.04172M solution of sodium chloride as the solvent. What are the concentrations of Cu⁺¹(aq) and Cl^-1(aq) ions in the saturated solution?

Answer 1

Copper(I) chloride = CuCl

CuCl(s) <==> Cu⁺(aq) + Cl^-(aq)

Ksp = [Cu⁺][Cl^-]

Since the solution contains a common ion (Cl^- from NaCl), we know the [Cl^-] will be 0.04172 M. We assume this to be the case since the CuCl is relatively insoluble (Ksp = 10^-6), so all of the Cl^- can be considered to come from the impure water.

1.248x10^-6 = [Cu⁺][0.04172]

[Cu⁺] = 2.99x10^-5 M

[Cl^-] = 0.04172 M