Gases can be liquefied by:

Explain the liquefaction of $CO_2$ gas using the Thomas Andrews plot,including the effects of temperature and pressure,and define the critical constants.

Critical temperatures for $A$,$B$,$C$ and $D$ gases are $25\,^{\circ}C$,$10\,^{\circ}C$,$-80\,^{\circ}C$ and $15\,^{\circ}C$ respectively. Which gas will be liquefied more easily?

Which of the following conditions is most favorable for the liquefaction of a gas?

The critical temperature of $O_2$ is $154.3 \ K$ and the critical temperature of $N_2$ is $126.0 \ K$. Which gas will liquefy first during the liquefaction of air?

Which of the following statements is incorrect?