Question

The ratio of rates of diffusion of helium and methane under same conditions of temperature and pressure will be

• A. $4:1$
• B. $2:1$
• C. $1:1$
• D. $1:2$

Answer 1

Answer: (B)

$2:1$

Answer 2

$\frac{r_{H e}}{r_{C H_{4}}}=\sqrt{\frac{M_{C H_{4}}}{M_{H e}}}$ $=\sqrt{\frac{16}{4}}=\sqrt{\frac{4}{1}}$ $=2: 1$