From a certain apparatus, the diffusion rate of hydrogen has an average value of 28.7 cm3 s-1. The diffusion of another gas under the same conditions is measured to have an average rate of 7.2 cm3 s-1. The gas is

Question

From a certain apparatus, the diffusion rate of hydrogen has an average value of 28.7 cm3 s-1. The diffusion of another gas under the same conditions is measured to have an average rate of 7.2 cm3 s-1. The gas is (A) Nitrogen (B) Helium (C) Argon (D) Oxygen

Tardigrade Admin · Accepted Answer

According to Graham's law of diffusion,

\frac{r _{1}}{r _{2}} = \frac{ρ _{2}}{ρ _{1}}

or

\frac{r _{1}}{r _{2}} = \frac{M _{2}}{M _{1}}

Here,

r_{1} =

diffusion rate of hydrogen

= 28.7 c m^{3} s^{- 1}

.

r_{2} =

diffusion rate of unknown gas

= 7.2 c m^{3} s^{- 1}

.

M_{1} =

molecular mass of hydrogen

= 2 g

∴ \frac{28.7}{7.2} = \frac{M _{2}}{2}

or

M_{2} = (\frac{28.7}{7.2})^{2} \times 2 ≃ 32 g

32 g

is molecular mass of oxygen.

Q. From a certain apparatus, the diffusion rate of hydrogen has an average value of 28.7cm3s−1. The diffusion of another gas under the same conditions is measured to have an average rate of 7.2cm3s−1. The gas is

Nitrogen

Helium

Argon

Oxygen

Q. From a certain apparatus, the diffusion rate of hydrogen has an average value of $28.7 c m^{3} s^{- 1}$ . The diffusion of another gas under the same conditions is measured to have an average rate of $7.2 c m^{3} s^{- 1}$ . The gas is