Variable valency of transition element is on account of

The valence shell of transition element consists of

The valence shell of transition element consists of

The valence shell of transition element consists of

Variable valency is shown by

The variability of oxidation states of transition elements arises out of:

Variable valency is characteristic of

Assertion : Transition metals show variable valency. Reason : Transition metals have a large energy difference between the ns^2 and (n-1)d electrons.