Question

$50$ volume of hydrogen take $20$ minutes diffuse out of a vessel. How long will $40$$ volume of oxygen take to diffuse out fro the same vessel under the same conditions?

Answer 1

Rate of diffusion for hydrogen, $r_1=\frac{50}{20}$
Rate of diffusion for oxygen, $r_2=\frac{40}{t}$
Mol. mass of hydrogen $=2$
Mol. mass of oxygen $=32$
So $\frac{50/20}{40/t}=\sqrt{\frac{32}{2}}$
or $\frac{50}{20}\times \frac{t}{40}=4$
$t=64minute$