Number of Faradays required to convert 1 mol of `Cr_(2)O_(7)^(2-)` into `Cr^(3+)` ions is :

Explanation

To determine the number of Faradays required to convert 1 mole of \( \text{Cr}_2\text{O}_7^{2-} \) into \( \text{Cr}^{3+} \) ions, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the oxidation states of chromium in \( \text{Cr}_2\text{O}_7^{2-} \)**:
- In \( \text{Cr}_2\text{O}_7^{2-} \), there are 7 oxygen atoms, each with an oxidation state of -2. Therefore, the total contribution from oxygen is \( 7 \times (-2) = -14 \).
- Let the oxidation state of chromium be \( x \). Since there are 2 chromium atoms, the total contribution from chromium is \( 2x \).
- The overall charge of the ion is -2, so we can set up the equation:
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