Question

The ratio of rate of diffusion of hydrogen and helium gas is

• A. $1:1.4$
• B. $1:1$
• C. $1.4:1$
• D. $1:2$

Answer 1

Answer: (C)

$\because \frac{r_H}{r_{He}}=\sqrt{\frac{M_{He}}{M_H}}$
$=\sqrt{\frac{4}{2}}=\sqrt{2}=1.4$
$\therefore r_H:r_{He}=1.4:1$