JEE Mains · Chemistry · STD 12 - 2. Electrochemistry
The quantity of electricity in Faraday needed reduce \(1\, mol\) of \(Cr _{2} O _{7}^{2-}\) to \(Cr ^{3+}\) is ....
- A \(50\)
- B \(6\)
- C \(600\)
- D \(300\)
Answer & Solution
Correct Answer
(B) \(6\)
Step-by-step Solution
Detailed explanation
\(Cr _{2} O _{7}^{-2}+6 e ^{-} \longrightarrow 2 Cr ^{+3}\) \(1 \,mol \quad 6\, mol\) \(\Rightarrow\) number of faradays \(=\) moles of electrons \(=6\)
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