JEE Mains · Chemistry · STD 12 - 2. Electrochemistry
An acidic solution of dichromate is electrolyzed for \(8\) minutes using \(2\) \(A\) current. As per the following equation \(Cr _{2} O _{7}^{2-}+14 H ^{+}+6 e ^{-} \rightarrow 2 Cr ^{3+}+7 H _{2} O\) The amount of \(Cr ^{3+}\) obtained was \(0.104\, g\). The efficiency of the process(in\%) is (Take : \(F =96000\, C\), At. mass of chromium \(=52\) )
- A \(60\)
- B \(56\)
- C \(64\)
- D \(50\)
Answer & Solution
Correct Answer
(A) \(60\)
Step-by-step Solution
Detailed explanation
Moles of \(e ^{\ominus}=\left(\frac{8 \times 60 \times 2}{96000}\right)\) Using stoichiometry; theoritically \(\frac{ n _{ e ^{\ominus}} used }{6}=\)\(\frac{ n _{ cr ^{+3}} \text {produced }}{2}\) \(\Rightarrow n _{ cr ^{+3}}\) produced…
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