Question

How many unpaired electron(s) are there in $N{i}^{2+}$ ion if the atomic number of Ni is 28

• A. 2
• B. 3
• C. 4
• D. 1

Answer 1

The correct option is A 2

Atomic number of $Ni$ = 28
So electronic configuration of $Ni$, $Ni=\left[Ar\right]3d^{8}4s^2$
Electronic configuration of $N{i}^{2+}$ wll be, $N{i}^{2+}=\left[Ar\right]3d^{8}4s^0$