Question:
Nitric acid is an oxidising agent and reacts with PbO but it does not react with PbO2. Explain why?
Solution:
Nitric acid is an oxidizing agent and reacts with PbO to give a simple acid-base reaction without any change in oxidation state. In PbO2, Pb is in +4 oxidation state and cannot be oxidized further, hence no reaction takes place between PbO2 and HNO3.