Why are Mn2+ compounds more stable than Fe2+ towards oxidation to their +3 state?
Answers
Electronic configuration of Mn2+ is [Ar]18 3d5.
Electronic configuration of Fe2+ is [Ar]18 3d6.
It is known that half-filled and fully-filled orbitals are more stable. Therefore, Mn in (+2) state has a stable d5 configuration. This is the reason Mn2+shows resistance to oxidation to Mn3+. Also, Fe2+has 3d6 configuration and by losing one electron, its configuration changes to a more stable 3d5 configuration. Therefore, Fe2+ easily gets oxidized to Fe+3 oxidation state.
AnswerMn+2 is more stable.
Explanation:this is due to the stability of 5 electrons in the D orbital of Mn. It will require high ionization enthalapy for Mn to loose one more electron from its D orbital. But in the case of Fe+2 it'll attain half filled configuration at +3 oxidation state.