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प्रश्न
Give reasons:
E° value for the Mn3+/Mn2+ couple is much more positive than that for Fe3+/Fe2+.
Assign reason for each of the following:
E° for the Mn3+/Mn2+ couple is much more positive than for Fe3+/Fe2+.
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उत्तर
- The standard electrode potential (E°) for Mn3+/Mn2+ is more positive than for Fe3+/Fe2+.
- Mn3+ is less stable and easily reduces to Mn2+, making its E° more positive.
- Fe3+ is relatively more stable and does not reduce as easily to Fe2+.
- The higher positive E° value for Mn3+/Mn2+ means Mn3+ is a stronger oxidizing agent than Fe3+.
- This difference arises because Mn3+ has a greater tendency to gain electrons and revert to the more stable Mn2+ state, while Fe3+ has comparatively less tendency to get reduced.
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