Question

Why do the transition elements exhibit higher enthalpies of atomisation?

Answer 1

$\text{Enthalpy of atomization}$

Enthalpy of atomization, ${\Delta }_a{H}^0$, is the change in enthalpy when one mole of bonds is completely broken to obtain atoms in the gas phase.

$\text{Enthalpy of atomization of transition elements}$

Because of large number of unpaired electrons in their atoms, transition elements have stronger interatomic interaction and hence stronger bonding between atoms resulting in higher enthalpies of atomization.