Pb3O4 + 4 HNO3 ----> Pb(NO3)2 + 2PbO2 + 2H2O?

Question

Explain how this reaction illustrates the relative basicities of the two oxidation states of lead.

Answer 1

Pb3O4 is a mixed oxide, and is assumed to contain both PbO and PbO2. The PbO part reacts to form Pb(NO3)2, but the PbO2 part is left behind because it's less basic. In fact, it's acidic!