Question

Which one of the following ions has an electronic configuration of $\left[Ar\right]3d^{10}$ ?

• A. $N{i}^{2+}$
• B. $M{n}^{2+}$
• C. $F{e}^{2+}$
• D. $Z{n}^{2+}$

Answer 1

The correct option is D $Z{n}^{2+}$

Electronic configurations of elements as per the Aufbau Principle:
Atomic number of Ni = 28
$N{i}^{2+}=\left[Ar\right]3d^8$
Atomic number of Mn = 25
$M{n}^{2+}=\left[Ar\right]3d^5$
Atomic number of Fe = 26
$F{e}^{2+}=\left[Ar\right]3d^6$
Atpmic number of Zn = 30
$Z{n}^{2+}=\left[Ar\right]3d^{10}$
$Z{n}^{2+}$ will have the required electronic configuration