(C) Actinium $(Ac)$ has the atomic number $89$.The electronic configuration of $Ac$ is $[Rn] \ 6d^1 \ 7s^2$.Due to the stability of its electronic con

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

(C) Actinium $(Ac)$ has the atomic number $89$.The electronic configuration of $Ac$ is $[Rn] \ 6d^1 \ 7s^2$.Due to the stability of its electronic configuration,it exhibits only a $+3$ oxidation state.In contrast,$Th$ $(Z=90)$ exhibits $+3$ and $+4$,$Pa$ $(Z=91)$ exhibits $+3, +4, +5$,and $U$ $(Z=92)$ exhibits $+3, +4, +5, +6$ oxidation states.