Question

What is the ratio of the rate of diffusion of helium gas to that of oxygen under identical conditions?

• A. 1 : 8
• B. 8 : 1
• C. 2 $\sqrt{2}$ : 1
• D. 1 : 2$\sqrt{2}$

Answer 1

Answer: (C)

2 $\sqrt{2}$ : 1

Rate of diffusion can be given as; $\sqrt{\frac{R_1}{R_2}}=\sqrt{\frac{M_2}{M_1}}$
$R_1$ = rate of diffusion of helium gas and $R_2$ = rate of diffusion of oxygen gas
$M_1$ = mass of helium gas and $M_2$ = mass of oxygen gas
Therefore $\sqrt{\frac{R_1}{R_2}}=\sqrt{\frac{16}{2}}$
$\sqrt{\frac{R_1}{R_2}}=\sqrt{\frac{8}{1}}$
$\sqrt{\frac{R_1}{R_2}}=2\sqrt{2}:1$