The electronic configuration of $Cr^{3+}$ is

Gadolinium (atomic number $= 64$) is a member of the $4f$ series. Its electronic configuration in the $+3$ oxidation state is $[Xe] 4f^7$. What is the ground state electronic configuration of gadolinium?

Which one of the following ions has the same number of unpaired electrons as those present in $V^{3+}$ ion?

Which elements were named by the following?
$(i)$ Lawrence Berkeley Laboratory
$(ii)$ Seaborg's group

What are the different possible oxidation states exhibited by scandium $(Sc)$?

The electronic configuration of transition element $X$ is $[Ar] 3d^5$,and its oxidation state is $+3$. What is its atomic number?