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प्रश्न
Why are Mn2+ compounds more stable than Fe2+ towards oxidation to their +3 state?
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उत्तर
- The electronic configuration of Mn2+ is [Ar] 3d5 while that of Fe2+ is [Ar] 3d6.
- Since Mn2+ has a half-filled orbit (3d5), it is not easily oxidised to Mn3+ because of its very high third ionization enthalpy.
- In contrast, Fe2+ compounds are easily oxidised to Fe3+ due to a lower third ionization enthalpy, which results in the more stable half-filled 3d5 configuration.
- This is the reason why Mn2+ compounds are more stable than Fe2+ towards oxidation to their +3 state.
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