Question

Why do the elements present in the middle of a transition series exhibit the maximum paramagnetic behaviour?

Answer 1

1. Transition elements have unpaired electrons in their (n − 1)d orbitals.
2. The number of unpaired electrons increases from one to five as we move from the beginning toward the middle of a transition series.
3. Maximum paramagnetism is observed in the middle of the series due to the maximum number of unpaired electrons.
4. After the middle, the number of unpaired electrons decreases, so paramagnetic behavior also decreases.
5. Elements with paired electrons show diamagnetic behavior, i.e., no paramagnetism.

Therefore, elements in the middle of a transition series exhibit the maximum paramagnetic behavior due to the highest number of unpaired d-electrons.