3.2 Properties of Solids

The melting point of a solid is the temperature at which it changes from a solid into a liquid. If a substance has stronger intermolecular forces, then it will generally have a higher melting point because more energy is needed to separate the particles enough for the solid to melt. The same idea applies to boiling point, which is the temperature at which a liquid becomes a gas. Stronger attractions between particles mean more energy is needed to completely separate them into the gas phase. It is important to note that melting mainly involves rearranging particles, while boiling requires separating them much more fully, so intermolecular forces often have an even greater effect on boiling point than on melting point.