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NTA Abhyas JEE Main2020Chemistryd and f Block ElementsPractice

Hydrogen peroxide acts both as an oxidising and as a reducing agent depending upon the nature of the reacting species. In which of the following cases H 2 O 2 acts as a most suitable reducing agent in acid medium ?

Options

  1. AKI
  2. BCr 2 O 7 2 -
  3. CS O 3 2 -
  4. DMn O 4 -

Correct answer

D. Mn O 4 -

Step-by-step solution

MnO 4 - + 8 H + + 5 e - → Mn 2 + + 4 H 2 O H 2 O 2 → O 2 + 2 H + + 2 e - H 2 O 2 acts as reducing agent gets oxidised H 2 O 2 → K 2 Cr 2 O 7 CrO 5 CrO 5 formation possibility is there, so K 2 Cr 2 O 7 not selected as choice but KMnO 4 selected.

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