CHEMISTRY GUIDE

This page looks at how the equilibrium between a liquid (or a solid) and its vapour leads to the idea of a saturated vapour pressure. It also looks at how saturated vapour pressure varies with temperature, and the relationship between saturated vapour pressure and boiling point. The origin of saturated vapour pressure The evaporation of a liquid The average energy of the particles in a liquid is governed by the temperature. The higher the temperature, the higher the average energy. But within that average, some particles have energies higher than the average, and others have energies lower than the average. Some of the more energetic particles on the surface of the liquid can be moving fast enough to escape from the attractive forces holding the liquid together. They evaporate. The diagram shows a small region of a liquid near its surface. ...