A helium atom is two times heavier than a hydrogen molecule. At 298 K, the average kinetic energy of a helium atom is-

1. Same as that of a hydrogen molecule

2. Half that of a hydrogen molecule

3. Two times that of a hydrogen molecule 

4. Four times that of a hydrogen molecule 

A 2.24 L cylinder of oxygen at STP is found to develop a leakage. When the leakage was plugged, the pressure dropped to 570 mm of Hg. The number of moles of gas that escaped will be:

1. 0.050

2. 0.025

3. 0.075

4. 0.01

The compressibility factor for 1 mol of a van der Waals gas at $0°\mathrm{C}$ and 100 atmospheric pressure is found to be 0.5. The volume of gas is-

1. 2.0224 L

2. 1.4666 L

3. 0.8542 L

4. 0.1119 L

At 0^°C, the density of a certain oxide of a gas at 2 bar is the same as that of dinitrogen at 5 bar.

The molecular mass of the oxide would be -

1. 35 g/mol

2. 45 g/mol

3. 70 g/mol

4. 60 g/mol

The pressure exerted by a mixture of 3.2 g of methane and 4.4 g of carbon dioxide contained in a 9 dm³ flask at 27 °C would be -

$1.$ $8.31$ $\times$ ${10}^4$ $\mathrm{Pa}$
$2.$ $7.43$ $\times$ ${10}^{-4}$ $\mathrm{Pa}$
$3.$ $6.87$ $\times$ ${10}^3$ $\mathrm{Pa}$
$4.$ $8.31$ $\times$ ${10}^6$ $\mathrm{Pa}$

Van der Waals parameter 'a' signifies -

1.The magnitude of intermolecular attractive forces.

2. The magnitude of intermolecular repulsive forces.

3. The volume of a gas molecule.

4. All of the above.

A plot of volume versus temperature (T) for a gas at constant pressure is a straight line passing through the origin. The plots at different values of pressure are shown in the figure given below.

       

The correct order of pressure is -

         Temperature (K) 

1. ${\mathrm{p}}_1>{\mathrm{p}}_2>{\mathrm{p}}_3>{\mathrm{p}}_4$

2. ${\mathrm{p}}_1={\mathrm{p}}_2={\mathrm{p}}_3={\mathrm{p}}_4$

3. ${\mathrm{p}}_1<{\mathrm{p}}_2<{\mathrm{p}}_3<{\mathrm{p}}_4$

4. ${\mathrm{p}}_1<{\mathrm{p}}_2={\mathrm{p}}_3<{\mathrm{p}}_4$

Gases possess characteristic critical temperature which depends upon the magnitude of intermolecular forces between the particles. Following are the critical temperatures of some gases.

From the above data, the order of liquefaction of the given gases is-
(write the order from the gas liquefying first)
1. ${\mathrm{H}}_2,$ $\mathrm{He},$ ${\mathrm{O}}_2,$ ${\mathrm{N}}_2$
2. $\mathrm{He},$ ${\mathrm{O}}_2,$ ${\mathrm{H}}_2,$ ${\mathrm{N}}_2$
3. ${\mathrm{N}}_2,$ ${\mathrm{O}}_2,$ $\mathrm{He,}$ ${\mathrm{H}}_2$
4. ${\mathrm{O}}_2,$ ${\mathrm{N}}_2,$ ${\mathrm{H}}_2,$ $\mathrm{He}$

The SI unit of viscosity coefficient $\left(\mathrm{\eta }\right)$ is-

1. Pascal

2. Nsm^-2

3. km^-2s

4. Nm^-2

With increase in temperature the surface tension of a liquid will:

1. Remains same

2. Decreases

3. Increases

4. No regular pattern is followed