Question

Give any two reasons for the formation of large number of complex compounds by transition metals.

Answer 1

Transition elements have a tendency to form, complexes than $S$ and $P$ block elements, which form only a few complexes.

The reason is:

1) They have small, highly charged ions.

2) They have vacant low energy orbitals to accept lone pairs of $e^{-}$'s donated by other groups or ligand.