<u>Melting point</u> is defined as the temperature at which solid and liquid phases are in equilibrium. It is the temperature at which a solid changes state from solid to liquid at atmospheric pressure.
<u>Boiling poin</u>t is the temperature at which the vapour pressure of a liquid is equal to the external pressure. It is the temperature at which a substance changes from a liquid into a gas.
<u>The flash point </u>of a flammable liquid or volatile liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.
Flashpoint mainly applies to volatile substances. It describes the lowest temperatures at which the vapors of the substance can ignite with the slightest spark. The melting point is the temperatures at which a substance changes phase from solid to liquid while the boiling point is the temperatures where a substance changes phase from liquid to gas.
