JEE Main202310 Apr 2023Evening ShiftChemistryRedox ReactionsActual

In alkaline medium, the reduction of permanganate anion involves a gain of ____________ electrons.

Correct answer

Step-by-step solution

In Faintly alkaline medium potassium permanganate changes to manganese dioxide in its oxidising action. MnO 4 - + 2 H 2 O + 3 e - → MnO 2 + 4 OH - The oxidation state of manganese in MnO 4 - is +7 and in MnO 2 is +4. Hence, it transfers 3 electrons during the oxidising action in alkaline medium.

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