There occurs much more frequent metal-metal bonding in compounds of heavy transition metals (i.e.,3^rd series).

Question

Explain the following observations giving an appropriate reason for each :

There occurs much more frequent metal-metal bonding in compounds of heavy transition metals (i.e.,3^rd series).

Answer 1

4d and 5d transition elements (2nd and 3rd series) are Iarger in size than the corresponding 3d elements. Hence the valence electrons are less tightly held and form M-M bond more frequently.