Question

The common oxidation state of Mn and Fe are +2 and +3 respectively. This is due to the

• A. stability of fully filled orbital
• B. stability of half filled orbital
• C. Inert pair effect
• D. None of the above

Answer 1

The correct option is B stability of half filled orbital

Atomic number of Fe - 26
$\text{Outer electronic configuration of}Fe=3d^{6}4s^2$
$\text{Outer electronic configuration of}F{e}^{3+}=3d^5$

Atomic number of Mn - 25
$\text{Outer electronic configuration of}Mn=3d^{5}4s^2$
$\text{Outer electronic configuration of}M{n}^{2+}=3d^5$

Due to the stability of half filled orbitals the common oxidation state of Mn and Fe are +2 and +3 respectively.