Question

why Tin (II) is a reducing agent but Pb (II) is not. explain in a simple way

Answer 1

For the elements like Sn and Pb to be reducing in (II) state ; they must have stable (IV) state as;

In reducing agent M⁺² -> M⁺⁴ + 2e^-

Now, we know that the inert pair effect increases down the group , so the stability of +4 oxidation state decreases down the group and hence the +4 oxidation state of Pb is less stable than that of Sn .

So, it becomes little difficult for Pb to get converted into its +4 state from its +2 state, so it does not behave as reducing agent.