The charge required for the reduction of 1 mol of \( MnO_4^- \) to \( MnO_2 \) is
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- 1 F
- 3 F
- 5 F
- 6 F
The Correct Option is C
Solution and Explanation
Step 1: In the reduction of \( MnO_4^- \) to \( MnO_2 \), the manganese ion undergoes a change in oxidation state from +7 to +4, which requires 5 moles of electrons. Hence, the charge required is 5 F (Faradays).
Step 2: Thus, the correct answer is option (3).
Top Questions on Electrochemistry
Standard electrode potential for \( \text{Sn}^{4+}/\text{Sn}^{2+} \) couple is +0.15 V and that for the \( \text{Cr}^{3+}/\text{Cr} \) couple is -0.74 V. The two couples in their standard states are connected to make a cell. The cell potential will be:
To calculate the cell potential (\( E^\circ_{\text{cell}} \)), we use the standard electrode potentials of the given redox couples.
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