PbO and `PbO_(2)` react with HCl according to following chemical equations
`2PbO+4HCl to2PbCl_(2)+2H_(2)O`
`PbO_(2)+4HCl toPbCl_(2)+Cl_(2)+2H_(2)O`
Why do these compounds differ n their reactivity?

Explanation

Writing the O.N of each element above its symbol in the following reaction s we have
in raction (i) O.N of none of the atoms undergo change therefore it is not a ardox reeaction it is fact an acid base reaction since `PbO_(2)` being a basic with HCI to form `PbCI_(2)` and `H_(2)O`
`PbO+2HCIrarrPbCI_(2)+H_(2)O`
in reaction (ii) Pb in `PbO_(2)` is present in +4 oxidation state since due to inert pari effect +2 oxide state of Pb is moire stable therefore `PbO_(2)` acts as an oxidisning agent as resutl it oxidises `CDI^(-) to CI_(2)` itself gets reduced to `Pb^(2+)` in tother words reaction of `PbO_(2)` with HCI is a redox reaction `PbO_(2) +4 HCI rarrPbCI_(2) +CI_(2)+2H_(2)O`
Thus the two compuntds differ in their reactivity beacuse they undergo different types of reactions