QJEEM21Ch3c6f: JEE Main 2021 Chemistry - Class 12 JEEM21Ch3c6f Solution: The number of 4f electrons in the ground statement electronic…

The electronic configuration of

$_{64}Gd:[Xe]4{f^7}5{d^1}6{s^2}$

So, the electronic configuration of

$_{64}G{d^{2 + }}:[Xe]4{f^7}5{d^1}6{s^0}$

i.e. the number of 4f electrons in the ground state electronic configuration of $G{d^{2 + }}$ is 7.