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JEE Main202226 Jul 2022Morning ShiftChemistryd and f Block ElementsActual

The dark purple colour of KMnO 4 disappears in the titration with oxalic acid in acidic medium. The overall change in the oxidation number of manganese in the reaction is

Options

  1. A5
  2. B1
  3. C7
  4. D2

Correct answer

A. 5

Step-by-step solution

The overall reaction takes place in the process is 2 KMnO 4 + 3 H 2 SO 4 + 5 COOH 2 → K 2 SO 4 + 2 MnSO 4 + 8 H 2 O + 10 CO 2 ↑ Potassium permanganate is a strong oxidising agent and in the presence of sulfuric acid it acts as a powerful oxidising agent. In acidic medium the oxidising ability of KMnO 4 is represented by the following equation. MnO 4 - + 8 H + + 5 e - → Mn 2 + + 4 H 2 O

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