How is the variability in oxidation states fo transition metals different from that of the non transition metaals?
Illustrate with examples.

Explanation

The variability in oxidation states of transition metals is due to the incomplete filling of d-orbitals in such a way that their oxidation states differ from each other by unity, e.g., `Fe^(2+)` and `Fe^(3+), Cu^(+)` and `Cu^(2+)` and `Cu^(2+)` etc. In case of non-transition elements, the oxidation states differ by units of two , e.g., `Pb^(2+)` and `Pb^(4+), Sn^(2+)` and `Sn^(4+)` etc. Moreover , in transition elements, the higher oxidation states are more stable for heavier elements in a group. For example , in group 6, Mo(VI) and W(VI) are more stable than Cr(VI) . In p-block elements , the lower oxidation states are more stable for heavier members due to inert pair effect, e.g., in group 16, Pb (II) is more stable than Pb(IV).