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. ${\mathrm{O}}_2,$ ${\mathrm{N}}_2,$ ${\mathrm{H}}_2,$ $\mathrm{He}$

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

1. Remains same

2. Decreases

3. Increases

4. No regular pattern is followed

 Among water, ether, and acetone, water has the maximum boiling point and ether has the minimum boiling point. The correct order of vapour pressure of water, acetone and ether at $30°\mathrm{C}$ is-

1. Water<ether<acetone

2. Water<acetone<ether

3. Ether<acetone<water

4. Acetone<ether<water

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

1. Pascal

2. Nsm^-2

3. km^-2s

4. Nm^-2

Maximum deviation from ideal gas is shown by-

1. H_2(g)   

2. N_2(g)

3. CH_4(g)

4. NH_3(g)