Why do transition metals have high enthalpies of atomization ?

Why do the transition elements have higher enthalpies of atomisation? In 3d series (Sc to Zn), which element has the lowest enthalpy of atomisation and why?

How would you account for the following : The transition elements exhibit high enthalpy of atomization.

Why transition metals are generally coloured ?

Why 5d transition series elements have higher ionization enthalpies than 4d transition series elements ?

Transition metals have high melting and boiling points. Why ?

Transition element and their compounds exhibit paramagnetic behaviour and transition metals have high melting points. Explain.

The transition elements have high melting points.