Question

The mixing of which pair of reactants will result in a precipitation reaction? a) NH4Cl(aq) + NH4I(aq) b) K2SO4(aq) + Cu(NO3)2(aq) c) Cu(NO3)2(aq) + K2CO3(aq) d) NaClO4(aq) + (NH4)2S(aq)