One of the assumptions of the kinetic theory of gases is that there is no force of attraction between the molecules of a gas. State and explain the evidence that shows that this assumption is not applicable for real gases.

(N/A) The kinetic theory of gases assumes that gas molecules do not exert any force of attraction on each other. However,this assumption fails for real gases because they can be liquefied by cooling and applying high pressure.
If there were no intermolecular forces of attraction,it would be impossible to liquefy a gas,as the molecules would not come together to form a liquid phase. The existence of intermolecular forces,such as van der Waals forces or hydrogen bonding (e.g.,in $HF$),allows molecules to aggregate,leading to liquefaction.
Evidence: The process of liquefaction of gases like $NH_3$,$CO_2$,and $Cl_2$ under high pressure and low temperature provides direct evidence that intermolecular forces of attraction exist in real gases.