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

Options

A. the 5forbitals extend farther from the nucles than 4f orbitals.
B. the 5f orbitals are more buried than the 4f orbitals.
C. there is similarity between 4f and 5f orbitals in their angular part of the wave function
D. the actinoids are more reactive than the lanthanoids.

Answer

A

Explanation

A ctinoids exhibits higher oxidation state compared to lanthanoids because Sforbitals are extended into space beyond 6s and 6p orbitals. The energies of Sfand 6d orbitals are very close hence they participate in bonding while in lanthanoids 4forbitals are buried deep inside the nucleus, totally shielded by outer orbitals and unable to take part in bonding