To what extent do the electronic configurations, decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.

Explanation

In a transition series, the oxidation states which result in half filled and completely filled d-subshell are more stable. For example, in the first transition series, electronic configuration of Mn (Z = 25) is `[Ar] 3d^(5) 4s^2` . 4s. It shows oxidation states from +2 to +7 but Mn (II) is most stable because it has stable electronic configuration. Similarly, we can say Zn (Z = 30) having electronic configuration `[Ar] 3d^(10) 4s^2` exhibits stable +2 oxidation state because of stable completely filled `3d^10 ` configuration.