Question

Solve this :

$$\begin{gathered} If{n}_1,n_{2}and{n}_{3}denotethenumberofunpairedelectronsinF{e}^{2+},M{n}^{2+}and{V}^{4+}respectively,thenwhichoneofthefollowingiscorrectrelationbetween{n}_1,n_{2}and{n}_3? \\ {n}_1=n_2>n_3 \\ {n}_1>n_2>n_3 \\ {n}_1=n_2=n_3 \\ {n}_2>n_1>n_3 \end{gathered}$$

Answer 1

Dear Student,

As the valence electronic configuration for the ions are as follows:

$$\begin{gathered} Fe-\left[Ar\right]3d^6,4s^2 \\ F{e}^{2+}-\left[Ar\right]3d^6,4s^0 \\ Mn-\left[Ar\right]3d^5,4s^2 \\ M{n}^{2+}-\left[Ar\right]3d^5,4s^0 \\ V-\left[Ar\right]3d^3,4s^2 \\ {V}^{4+}-\left[Ar\right]3d^1,4s^0 \end{gathered}$$

So the unpaired electrons are as follows:
Fe²⁺ has 4 unpaired electrons
Mn^2+​​​ has 5 unpaired electrons
V⁴⁺ has 1 unpaired electrons


So, $n_2>n_1>n_3$

Regards.