For Daily Free Study Material Join wiredfaculty Whatsapp Group | Download Android App | Ncert Book Download
The D-And-f-Block Elements
E° value for a Mn3+/Mn2+ couple is much more positive than that for Fe3+/Fe2+.
Mn3+/ Mn2+ has large + value because Mn3+ reduced to Mn+2 which has a half-filled d-orbital configuration ([Ar]4s03d5).
On the other hands, Fe3+/ Fe2+ has small +ve value because Fe3+ is much more stable than Fe2+. Electronic configuration of Fe3+ is [Ar]4s2 3d5 and Fe2+ [Ar]4s2 3d6.