One ampere of current is passed for 9650 seconds through molten $\mathrm{AlCl}_3$. What is the weight in…
One ampere of current is passed for 9650 seconds through molten $\mathrm{AlCl}_3$. What is the weight in grams of $\mathrm{Al}$ deposited at cathode? (atomic weight of $\mathrm{Al}=27$ )
$0.9$
$9.0$
$0.09$
$90.0$
Solution
$\begin{aligned} & \text { Gram equivalent weight of } \mathrm{Al}=\frac{27}{3}=9 \mathrm{~g} \\ & \qquad \begin{aligned} z & =\frac{E}{96500}=\frac{9}{96500} \\ w & =z . i . t=1 \times \frac{9}{96500} \times 9650 \\ & =\frac{9}{10}=0.9 \mathrm{~g}\end{aligned}\end{aligned}$