Question

How many electrons are involved in the following redox reaction? \[ \text{Cr}_2\text{O}_7^{2-} + \text{Fe}^{2+} + \text{C}_2\text{O}_4^{2-} \rightarrow \text{Cr}^{3+} + \text{Fe}^{3+} + \text{CO}_2 \quad (\text{Unbalanced}) \] 
 

• A. \( 3 \)
• B. \( 4 \)
• C. \( 6 \)
• D. \( 5 \)

Hint:

When balancing redox reactions, determine oxidation states and use the half-reaction method to balance the number of electrons transferred.