Question

A specific volume of $H_2$ requires 24 s to diffuse out of a container. The time required by an equal volume of $O_2$ to diffuse out under identical conditions, is:

• A. 24 s
• B. 96 s
• C. 384 s
• D. 192 s

Answer 1

The correct option is B 96 s

Rate is volume diffused per unit time and is equal to square root of molar mass.
$\frac{V_{H2}}{t_{H2}}\times \frac{t_{O2}}{V_{O2}}=\sqrt{\frac{M_{O2}}{M_{H2}}}$
$\frac{V_{H2}}{24s}\times \frac{t_{O2}}{V_{H2}}=\sqrt{\frac{32}{2}}$
$\frac{1}{24s}\times \frac{t_{O2}}{1}=4$
$t_{O2}=4\times 24=96s$
The time required by an equal volume of O2 to diffuse out under identical conditions, is 96 s.