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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?

Short Answer
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Solution

  1. Manganese, having five unpaired electrons, exhibits six different oxidation states. The small energy difference between the 3d and 4s orbitals allows manganese to lose electrons from both, resulting in oxidation states ranging from +2 to +7.
  2. Electronic configuration of Mn2+ = [Ar]3d54s0
  3. Half-filled (d5) d-orbitals provide the Mn2+ ion additional stability, making Mn in the +2 oxidation state more stable.
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2012-2013 (March)

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