Question

The stability of ferric ion is due to

• A. half-filled d-orbitals
• B. half-filled f-orbitals
• C. completely filled d-orbitals
• D. completely filled f-orbitals

Answer 1

Answer: (A)

half-filled d-orbitals

Answer 2

$E.C$. of $Fe ^{3+}$ ion i.e., $Fe ^{3+}=1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{6}, 3 d^{5} .$ Therefore, ferric ion is quite stable due to half-filled $d$-orbitals.