Question

1) The molar solubility of copper(II) sulfide in a 0.266 M copper(II) acetate solution is _______ M.

2) The maximum amount of cobalt(II) carbonate that will dissolve in a 0.258 M cobalt(II) nitrate solution is _______  M.

Answer 1

1. CuS (s) ------------> Cu^2+ (aq) + S^2- (aq)

                                               s+0.266        s

    ksp   = [Cu^2+][S^2-]

    6*10^-37 = (s+0.266)(s)                                [s+0.266 = 0.266]

    6*10^-37   = 0.266*s

     s              = 6*10^-37/0.266   = 2.25*10^-36 M

2.   CoCO3(s) --------------------> Co^2+ (aq) + CO3^2-

                                                    s+0.258         s

        Ksp   = [Co^2+][CO3^2-]

     1*10^-10   = (s+0.258)(s)                                           {s +0.258 = 0.258)

1*10^-10       = 0.258*s

       s            = 1*10^-10/0.258   = 3.87*10^-10 M

solubility of cobalt(II) carbonate is 3.87*10^-10M