Question

# Explain the given reasons:(a)- Transition metals and many of their compounds show paramagnetic behavior.(b)- The enthalpies of the atomization of the transition metals are high.(c)- The transition metals generally form colored compounds.(d)- Transition metals and their many compounds act as a good catalyst.

Hint: If unpaired electrons are present in the compound then it shows paramagnetic behavior. Colored ions are formed due to the presence of unfilled d-subshell. The presence of unpaired electrons in the incomplete d-subshell helps to act as a good catalyst.

Color is due to the presence of incomplete d-subshell. Further, when the anion or the ligands approach the transition metal ions, their d-orbitals do not remain degenerated. They split into two sets, one consisting of lower energy orbitals (${{\text{t}}_{\text{2g}}}\text{which includes }{{\text{d}}_{\text{xy}}}\text{,}{{\text{d}}_{\text{yz}}}\text{,and }{{\text{d}}_{\text{zx}}}$) and the other consisting of higher energy orbitals (${{e}_{\text{g}}}\text{which includes }{{\text{d}}_{{{\text{x}}^{2}}-{{y}^{2}}}}\text{,and }{{\text{d}}_{{{\text{z}}^{2}}}}$). This is called crystal field splitting.