Question

Find the time required to liberate 1.0 litre of hydrogen at STP in an electrolytic cell by a current of 5.0 A.

Answer 1

Let the required time be t.
Mass of 1 litre hydrogen,
$m=\frac{2}{22.4}\mathrm{g}$
Using the formula, m = Zit, we get:
$$\begin{gathered} \frac{2}{22.4}=\frac{1\times 5\times t}{96500} \\ \Rightarrow t=\frac{2\times 96500}{22.4\times 5} \\ \Rightarrow t=1723.21\mathrm{s}=28.7\mathrm{minutes}\approx 29\mathrm{minutes} \end{gathered}$$