Vapour Liquid Equilibrium Pdf. The preceding section has described what is observed through experimental observation. Thus, at equilibrium, the rate of evaporation.
We say that the system has r eached equilibrium state at this stage. In this qualitative discussion, we limit consideration to systems comprised of two chemical species, because systems of greater complexity cannot be adequately represented graphically. Vapour pressure because of an equilibrium in which the number of molecules leaving the liquid equals the number retur ning to liquid fr om the vapour.