Same chapter3 marksDifficulty: Medium
Balance the following redox reaction in acidic medium by the ion-electron method: MnO4− + Fe2+ → Mn2+ + Fe3+.
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3 marksDifficulty: Medium
Find the oxidation number of manganese in KMnO4 and of chromium in K2Cr2O7.
Original Khojo Papers practice question — not from a past board paper.
Answer
+7 and +6 respectively
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
In KMnO4, 1 + x + 4(−2) = 0 gives x = +7. In K2Cr2O7, 2(1) + 2x + 7(−2) = 0 gives 2x = 12, so x = +6.
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