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Why +2 oxidation state of manganese is more stable? - Chemistry

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Question

Why +2 oxidation state of manganese is more stable?

Solution

Mn
Atomic number = 25
Mn2+
No. of electrons = 23

Electronic configuration of Mn2+ = [Ar]3d54s0

(1) It is seen from the electronic configuration of Mn2+ that d-orbital is half filled.

(2) A half filled d-orbital is more stable as compared to empty or partially filled orbital.

(3) Hence Mn2+ ion is more stable oxidation state of manganese.

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2012-2013 (March)

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