In acidic medium, H2O2 changes Cr2O7–2 to CrO5 which has two (–O – O–) bonds.
The oxidation state of Cr in CrO5 is:

1. +5

2. +3

3. +6

4. -10

Subtopic:  Chemistry of Mn and Cr Compounds |
 77%
Level 2: 60%+
AIPMT - 2014
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Considering the following reaction,
3 MnO 42– + 2 H 2 O ⇌ 2 MnO 4 + MnO 2 + 4 OH
The reagent that facilitates the removal of OH ions to ensure the completion of the conversion of K2MnO4 to KMnO4 is:

1. KOH
2. CO2
3. SO2
4. HCl
Subtopic:  Chemistry of Mn and Cr Compounds |
Level 3: 35%-60%
AIPMT - 2013
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