The average kinetic energy of a helium atom at $30°C$ is:                                                                                           [MP PMT 2004]

(1) Less than 1 eV

(2) A few KeV

(3) 50-60 eV

(4) 13.6 eV

The mean translational kinetic energy of a perfect gas molecule at the temperature T Kelvin is:

(1) $\frac{1}{2}kT$         (2) kT             (3) $\frac{3}{2}kT$            (4) 2 kT

One litre of gas A and two litres of gas B, both having the same temperature 100$°$C and the same pressure 2.5 bar will have the ratio of kinetic energies of their molecules as:

(1) 1:1       (2) 1:2       (3) 1:4         (4) 4:1

An ideal gas is filled in a vessel, then

(1) If it is placed inside a moving train, its temperature increases

(2) Its centre of mass moves randomly

(3) Its temperature remains constant in a moving car

(4) None of these

If P is the pressure of the gas then the KE per unit volume of the gas is:

1.  $\frac{P}{2}$

2.  $P$

3.  $\frac{3P}{2}$

4.  $2P$

A gas mixture consists of 2 moles of oxygen and 4 moles of argon at temperature T. Neglecting all vibrational modes, the total internal energy of the system is

1.  4RT

2.  15RT

3.  9RT

4.  11RT

For an ideal gas V-T curves at constant pressure ${\mathrm{P}}_1$ and ${\mathrm{P}}_2$ are shown in figure. From the figure

1. ${\mathrm{P}}_1>{\mathrm{P}}_2$

2. ${\mathrm{P}}_1<{\mathrm{P}}_2$

3. ${\mathrm{P}}_1={\mathrm{P}}_2$

4. ${\mathrm{P}}_1\le {\mathrm{P}}_2$

4.0 g of a gas occupies 22.4 L at NTP. The specific heat capacity of the gas at constant volume is 5.0 J K^-1mol^-1. If the speed of sound in this gas at NTP is$952 m{s}^{-1}$, then the heat capacity at constant pressure is: (Take gas constant R=8.3 JK^-1mol^-1)

(a) 8.0 JK^-1mol^-1

(b) 7.5 JK^-1mol^-1

(c) 7.0 JK^-1mol^-1

(d) 8.5 JK^-1mol^-1

The mean free path of gas A, with molecular diameter equal to 4 Å, contained in a vessel, at a pressure of ${10}^{–6}$ torr, is 6990 cm. The vessel is evacuated and then filled with gas B, with molecular diameter, equal to 2 Å, at a pressure of ${10}^{–3}$ torr, the temperature remaining the same. The mean free path of gas B will be

(A) 28 cm                       

(B) 280 cm

(C) 7 cm                         

(D) 14 cm

The mean free path of gas molecules depends on:
(\(d=\) molecular diameter)
1. \(d\)
2. \(d^2\)
3. \(d^{-2}\)
4. \(d^{-1}\)