Question:

The stability of ferric ion is due to:

completely filled f-orbitals

completely filled d-orbitals

half-filled d-orbitals

half-filled f-orbitals

Ferric ion Fe³⁺ has half-filled d orbitals. The electronic configuration of Fe is [Ar]3d⁶4s². The electronic configuration of Fe³⁺ is [Ar]3d⁵