How would you account for the fact that actinoids exhibit a larger number of oxidation state than the corresponding lanthanoids?

Explanation

Actinoids show a larger number of oxidation states because the energy gap between 5f, 6d and 7s subhsells is very small and hence all the electrons present in these subshells can participate in bonding whereas lanthanoids show a limited number of oxidation states because the energy gap between 4f and 5d subshells is large and all the electrons in these subshells cannot participate in bonding.