The numbers of the actinoid series exhibit a larger number of oxidation states than the corresponding members of the lanthanoid series.

Question

Explain the following observations :

The numbers of the actinoid series exhibit a larger number of oxidation states than the corresponding members of the lanthanoid series.

Answer 1

Actinoids exhibit a large number of oxidation states because 5f ,6d and 7s levels have almost comparable energies (very small energy difference between sub-shells than the energy difference between 4f and 5d orbitals in case of Lanthanoids.