According to Raoult's law, "The vapor pressure exerted by component in a solution is proportional to the mole fraction of that component." Raoult's law is not applicable under the following assumption/condition.

• No component is concentrated at the surface of the solution.
• The component molecules are non polar and are of almost equal size.
• In the formation of solution, chemical combination/molecular association between unlike molecules takes place.
• The attractive forces between like and unlike molecules are almost equal.