In 
physics, 
melting is the process of heating a 
solid substance to a point (called 
melting point) where it turns 
liquid. An object, which has melted, is 
molten. 
Freezing is the opposite of melting. It is the process of turning a liquid to a solid. Consequently the freezing point  is the same 
temperature as the melting point.See 
phase article for more detail.
In 
genetics, 
melting DNA means to separate the double-stranded DNA into two single strands by heating or the use of chemicals.
- See also : Polymerase chain reaction
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