Question

If the rate of effusion of helium gas at a pressure of $1000$ torr is $10$ torr $\min ^{-1}$. Find the rate of effusion of hydrogen gas at a pressure of $2000$ torr at the same temperature.

• A. 20 torr $\min ^{-1}$
• B. 10 torr $min ^{-1}$
• C. $30 \sqrt{2}$ torr $min ^{-1}$
• D. $20 \sqrt{2}$ torr $min ^{-1}$

Answer 1

Answer: (D)

At a given temperature, rate of effusion $P$ and $1 / \sqrt{M}$
Rate of effusion of hydrogen gas
$=10$ torr $\min ^{-1} \times \frac{2000}{1000} \times \sqrt{(4 / 2)}$
$=20 \sqrt{2}$ torr $\min ^{-1}$