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JEE Main202125 Jul 2021Evening ShiftChemistryRedox ReactionsActual

Identify the process in which change in the oxidation state is five :

Options

  1. ACr 2 O 7 2 - → 2 Cr 3 +
  2. BMnO 4 - → Mn 2 +
  3. CCrO 4 2 - → Cr 3 +
  4. DC 2 O 4 2 - → 2 CO 2

Correct answer

B. MnO 4 - → Mn 2 +

Step-by-step solution

MnO 4 - + 5 e → Mn + 2

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