A 3.0-L sample of helium was placed in container fitted with a porous membrane. Half of the helium effused through the membrane

Question

2 months ago

11

A 3.0-L sample of helium was placed in container fitted with a porous membrane. Half of the helium effused through the membrane

in 24 hours. A 3.0-L sample of oxygen was placed in an identical container. How many hours will it take for half of the oxygen to effuse through the membrane?

Chemistry

1 answer:

Tems11 [2.7K] · Answer 1 · 2026-03-11T15:22:37+03:00

Explanation:

The rate at which gases effuse is inversely related to the square root of their molar masses.

In this case, half of the helium (1.5 L) passed through the membrane in 24 hours. Therefore, we can calculate the effusion rate of He gas as follows.

$\frac{1.5 L}{24 hr}$

= 0.0625 L/hr

Given that the molar mass of He is 4 g/mol and for $O_{2}$ it is 32 g/mol.

Now,

$\frac{\text{Rate of He}}{\text{Rate of Oxygen}} = \sqrt{\frac{32}{4}$

= 2.83

Thus, the effusion rate of $O_{2} = \frac{\text{Rate of He}}{2.83}$

= $\frac{0.0625 L/hr}{2.83}$

Rate of $O_{2}$ = 0.022 L/hr.

This implies that 0.022 L of $O_{2}$ gas will effuse in one hour.

Consequently, to find the duration needed for 1.5 L of $O_{2}$ gas to effuse, we calculate as follows.

$\frac{1.5 L}{0.022 L/hr}$

= 68.18 hours

Thus, we can conclude that it will require 68.18 hours for half of the oxygen to effuse through the membrane.