Question

Determine the relative solubilities of the following copper(II) compounds: Қар — Relative Solubility, M Compound CuCoz Cus Cu(OH)2 2.5x10-10 7.9x10-37 1.6x10-19 Submit Answer

Answer 1

(a) The dissociation of Cuco, is given as follows: Cucoz (s) → Cu2+ (aq) +COŽ (aq) Since CuCoz is sparingly soluble salt, therefore, its solubility is given as s. The solubility product for this reaction is given as follows: K., =[Cu?+][co] 2.5x10-10 = (s)(s) s =1.58x10- Therefore, the solubility of Cuco, is 1.58x10 mol/L. (b) The dissociation of CuS is given as follows: Cus(s) → Cu2+ (aq) +S2- (aq) S s The solubility product for this reaction is given as follows: K = [cu?+ ][5] 7.9x10-31 = (s)(s) S = 8.89 x 10-19 Therefore, the solubility of Cuco, is 8.89x10 mol/L.

(c) The dissociation of Cu(OH), is given as follows: Cu(OH), (s) → Cu2+ (aq) +20H" (aq) s 2s The solubility product for this reaction is given as follows: K., -[Cu” ][OH-] 1.6x10-19 =(s) (25) S = 3.42x10-7 Therefore, the solubility of Cu(OH), is 3.42x10-7 mol/L. Therefore, Cuco, will have highest solubility. CuS will have lowest solubility. Cu(OH), will have intermediate solubility.