WBJEE · Chemistry · Redox Reactions
How many faradays are required to reduce \(1 \mathrm{mol}\) of \(\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}\) to \(\mathrm{Cr}^{3}\) - in acid medium?
- A 2
- B 3
- C 5
- D 6
Answer & Solution
Correct Answer
(D) 6
Step-by-step Solution
Detailed explanation
\(\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-} \longrightarrow \mathrm{Cr}^{3}\) " Change in +3 Oxi no. \(=+6\) Total change in number of electrons \(=2 \times 3=6 \mathrm{mole}=6 \mathrm{F}\)
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