Question

If Hund's rule is not followed, magnetic moment if Fe${}^{2+}$ is:

• A. 0
• B. $\frac{h}{2\pi }$
• C. $\frac{3h}{2\pi }$
• D. $\frac{\sqrt{3}h}{4\pi }$

Answer 1

The correct option is A 0

According to Hund's rule electrons are distributed among the orbitals of subshell in such a way as to give the maximum number of unpaired electron with parallel spin. i.e. in a subshell pairing of an electron will not start until and unless all the orbitals of that subshell will get one electron each with the same spin. So, $F{e}^{+2}$ have zero unpaired electrons and the magnetic moment is zero.