Q. Larger number of oxidation states are exhibited by the actinoides than those by the lanthanoides, the main reason being
A) 4$f$- orbitals more diffused than the 5$f$-orbitals
B) Lesser energy difference between 5$f\$and 6$d$ than between 4$f\$and 5$d$-orbitals
C) More energy difference between 5$f$ and 6$d$ than between 4$f$ and 5$d$-orbitals.
D) More reactive nature of the actinoides than the lanthanoides
Explanation
(b)
Lanthanoids [Xe]$4f^{1 - 14}5d^{0 - 1}\ 6s^{2}$
Actinoides [Rn]$5f^{1 - 14}6d^{0 - 1}7s^{2}$
Lanthanoides and actinoides use core $d$ and $f$-orbitals also to show higher oxidation state. As actinoides have comparatively low energy difference between $f\$and $d$-orbitals, show more oxidation states.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.