Question

If a solution containing 0.015 M each of bromide, chloride, iodide, and thiocyanate, is treated with Cu+, in what order will the anions precipitate?

Answer 1

Take CuBr as an example: The Ksp value is 6.3E-9 but make sure you use the Ksp values in your notes or your text.
................CuBr ===> Cu^+ + Br^-
I................solid...........0...........0
C..............solid............x............x
E..............solid.............x............x
Ksp = 6.3E-9 = (Cu^+)(Br^-)
(Cu^+) = x
(Br^-) = 0.15 M from the problem.
Substitute
6.3E-9 = (x)(0.15)..
Then x = (Cu^+) = 6.3E-9/0.15 = ?
Do the same for all of the salts. The one with the smallest value for Cu will ppt first followed in order by the others. Post your work if you get stuck.

Answer 2

Thank you so much for your help.