The Relation of Pressure to Molecular Energy

[miss photon]

when some molecules in a liquid gain enough energy to overcome attractive forces by surrounding molecules, they escape from the liquid surface. but when the vapor pressure becomes equal to atmospheric pressure, boiling is said to take place and all the molecules seem to gain sufficient energy to escape. what is the relation of pressure with 'energy' of the molecules? after all pressure is only thrust per unit area. how can it affect the energy of the molecules?

 

[Doc Al]

You increase the vapor pressure by raising the temperature of the liquid (by adding energy to it).