Melting point
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Melting point (or rarely liquefaction point) is a temperature at which the solid and liquid forms of a pure substance can exist in equilibrium.
Mechanism
As heat is applied to a solid, its temperature will increase until the melting point is reached. When more heat is added, a solid will change into a liquid with no temperature change. When all the solid has melted, additional heat will raise the temperature of the liquid. The melting temperature of crystalline solids is a characteristic figure and is used to identify pure compounds and elements. Most mixtures and amorphous solids melt over a range of temperatures. The melting point of a substance depends on pressure and is usually specified at standard pressure. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of some substances to supercool, the freezing point is not considered as a characteristic property of a substance. When the "characteristic freezing point" of a substance is determined, in fact the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice", that is, the melting point.
