The actinoids exhibit, more member of oxidation states in general than the lanthanoids. This is because

Options

A. the actinides are more reactive than the lanthanides
B. the `5f`-orbits are more buried than the `4f`-orbits
C. there is a similarity between `4f`and `5f`-orbits in their angular part of the wave function.
D. the `5f`-orbits extend farther from the nucleus than the `4f`-orbitals.

Answer

D

Explanation

The wide range of oxidation state of actionids is due to the fact that the `5f, 6d` and `7s` energy levels are of comparable energies and all these three subshells can participated in comparsion to lanthanoid. The `5f` orbitals extend father from the nucleus than the `4f` orbitals.