Suppose that you wished to prepare copper(II) carbonate by a precipitation reaction involving Cu2+ and CO3^2-. Select all of the pairs of reactants that could be used as solutes:
A CuSO4 and (NH4)2CO3
B CuCl2 and K2CO3
C Cu(OH)2 and Na2CO3
D CuS and NiCO3
E Cu(NO3)2 and CaCO3