As dillution takes place

Options

A. oxidation potential decreases
B. reduction potential increases
C. oxidation potential increases
D. cell potential may increases

Explanation

To solve the question regarding the effects of dilution on electrode potentials, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Nernst Equation**:
The Nernst equation relates the electrode potential to the concentrations of the reactants and products. For a reduction reaction, it is given by:
\[ E = E^0 - \frac{2.303}{nF} \log \left( \frac{[Ox]}{[Red]} \right) \]
where \(E^0\) is the standard electrode potential, \(n\) is the number of electrons transferred, \(F\) is Faraday's constant, \([Ox]\) is the concentration of the oxidized form, and \([Red]\) is the concentration of the reduced form.

2. **Identifying the Reaction**:
In this case, we are looking at the reduction of Mn²⁺ to Mn. Therefore, we can rewrite the Nernst equation specifically for this reaction:
\[ E_{Mn^{2+}/Mn} = E^0_{Mn^{2+}/Mn} - \frac{2.303}{nF} \log \left( \frac{[Mn]}{[Mn^{2+}]} \right) \]

3. **Analyzing the Effect of Dilution**:
As dilution occurs, the concentration of Mn²⁺ (the oxidized form) decreases. This affects the logarithmic term in the Nernst equation:
\[ E_{Mn^{2+}/Mn} = E^0_{Mn^{2+}/Mn} - \frac{2.303}{nF} \log \left( \frac{[Mn]}{[Mn^{2+}]} \right) \]
- If \([Mn^{2+}]\) decreases (due to dilution), the term \(\log \left( \frac{[Mn]}{[Mn^{2+}]} \right)\) will become less negative (or more positive), leading to a decrease in the overall electrode potential \(E\).

4. **Conclusion on Reduction Potential**:
Therefore, as dilution increases, the reduction potential \(E_{Mn^{2+}/Mn}\) decreases.

5. **Considering Oxidation Potential**:
The oxidation potential can be derived similarly:
\[ E_{Mn/Mn^{2+}} = E^0_{Mn/Mn^{2+}} - \frac{2.303}{nF} \log \left( \frac{[Mn^{2+}]}{[Mn]} \right) \]
- As dilution increases, \([Mn^{2+}]\) decreases, which means that the logarithmic term becomes less negative (or more positive), leading to an increase in the oxidation potential \(E_{Mn/Mn^{2+}}\).

### Summary of Effects:
- **Reduction Potential**: Decreases with dilution.
- **Oxidation Potential**: Increases with dilution.