The mean free path \(l\) for a gas molecule depends upon the diameter, \(d\) of the molecule as:
1. | \(l\propto \dfrac{1}{d^2}\) | 2. | \(l\propto d\) |
3. | \(l\propto d^2 \) | 4. | \(l\propto \dfrac{1}{d}\) |
The mean free path for a gas, with molecular diameter \(d\) and number density \(n,\) can be expressed as:
1. \( \frac{1}{\sqrt{2} n \pi \mathrm{d}^2} \)
2. \( \frac{1}{\sqrt{2} n^2 \pi \mathrm{d}^2} \)
3. \(\frac{1}{\sqrt{2} n^2 \pi^2 d^2} \)
4. \( \frac{1}{\sqrt{2} n \pi \mathrm{d}}\)
If the mean free path of atoms is doubled , then the pressure of the gas will become:
1. P/4
2. P/2
3. P/8
4. P
If the pressure in a closed vessel is reduced by drawing out some gas, the mean free path of the molecules:
1. | decreases |
2. | increases |
3. | remains unchanged |
4. | increases or decreases according to the nature of the gas |
When the gas in an open container is heated, the mean free path:
1. | Increases |
2. | Decreases |
3. | Remains the same |
4. | Any of the above depending on the molar mass |
(A) | the motion of the gas molecules freezes at \(0^\circ\text C.\) |
(B) | the mean free path of gas molecules decreases if the density of molecules is increased. |
(C) | the mean free path of gas molecules increases if the temperature is increased keeping the pressure constant. |
(D) | \(\dfrac32k_B T\) (for monoatomic gases). | average kinetic energy per molecule per degree of freedom is
1. | (A) and (C) only |
2. | (B) and (C) only |
3. | (A) and (B) only |
4. | (C) and (D) only |