A mining operation needs to separate silver and copper. You are hired as a summer intern in a beautiful Colorado mining town, and one of your tasks is to determine whether this separation can be accomplished by oxidizing the metals to Ag⁺ and Cu⁺, each one at a concentration of 0.15 M, and then precipitate one as the chloride salt without precipitate the other. AgCl precipitates first. What is the concentration of the Ag⁺remaining in solution when CuCl begins to precipitate? For AgCl, pK_sp = 9.74. and for CuCl, pK_sp = 6.76.

Question

Quizplus · Accepted Answer

To find the concentration of Ag⁺ remaining when CuCl begins to precipitate, calculate the chloride ion concentration at which CuCl starts to precipitate using its K_sp. Then, use this chloride concentration to find the remaining Ag⁺ concentration using AgCl's K_sp. The calculations show that the concentration of Ag⁺ is 1.57 × 10^-4 M.

A Mining Operation Needs to Separate Silver and Copper