The reaction at cathode in the cells commonly used in clocks involves:
Electrochemistry · Class 12 · JEE Main Previous Year Question
The reaction at cathode in the cells commonly used in clocks involves:
- a
reduction of Mn from +7 to +2
- b✓
reduction of Mn from +4 to +3
- c
oxidation of Mn from +3 to +4
- d
oxidation of Mn from +2 to +7
reduction of Mn from +4 to +3
Strategy: Identify the components and chemistry of the Leclanché (dry) cell commonly used in clocks and remote controls.
Cell Chemistry:
- Anode: Zinc container ().
- Cathode: Carbon rod surrounded by powdered .
- Reaction at Cathode:
Oxidation States:
- In , Mn is .
- In , Mn is . There is a reduction from to .
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