The melting point of a body (a Métal in particular) represents the Température to which coexist its solid state and its liquid state. The melting point is a constant of a substance periodic of the elements. It is usually calculated under Atmospheric pressure normal (1 atmosphere). It is thus possible, by knowing its melting point, to determine the nature of a substance (identification).
The melting point is also a means of checking the Pureté of a substance: any impurity will vary the melting point of the substance tested.
When a solid substance is heated, it increases temperature until reaching the melting point. Once at the melting point, the temperature remains constant as long as the substance did not pass entirely under liquid phase. Then, the temperature of the substance, now liquid, continues to rise.
Contrary to the Temperature of vaporization (not of boiling), the melting point is rather insensitive with the changes of pressure.
Particular cases
Two enantiomers inevitably do not have the same melting point, and even often have two different melting points. In the same way for two polymorphic forms different.An amorphous substance does not have in general a melting point, because it does not undergo fusion itself but a vitreous transition.
Simple: Melting not Zh-yue: 冰點
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