Two electrolytic cells are connected in series containing C u S O 4 solution and molten A l C l 3 . If in electrolysis 0.4 moles of ‘ C u ’ are deposited on cathode of ﬁrst cell. The number of moles o

Question

Two electrolytic cells are connected in series containing C u S O 4 solution and molten A l C l 3 . If in electrolysis 0.4 moles of ‘ C u ’ are deposited on cathode of ﬁrst cell. The number of moles of ‘ A l ’ deposited on cathode of the second cell is

TestHub · Accepted Answer

According to Faraday’s second law of electrolysis:
$\frac{m_{c u}}{m_{A l}} = \frac{E_{c u}}{A_{A l}}$
$\frac{0.4 \times 63.5}{m_{A l}} = \frac{\frac{63.5}{2}}{\frac{27}{3}}$
$m_{A l} = 7.2 g$
$\Rightarrow$ No. of moles of $A l = n_{A l} = \frac{7.2}{27} = 0.27$
Hint: $E_{c u} = \frac{A t o m i c m a s s o f C u}{2}$ and $E_{A l} = \frac{A t o m i c m a s s o f A l}{3}$

Chemistry - Electrochemistry Question with Solution | TestHub

Options:

Doubts & Discussion