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Name: Miriam K.
Status: student
Age: 13
Location: N/A
Country: N/A
Date: 2/22/2004


Question:
Why is the meting point and freezing point of a pure substance the same?


Replies:
These are just different words to describe the same process, but in opposite directions.

Freezing point -------> liquid to solid

Melting point or Fusion point ------> solid to liquid

Vince Calder


Miriam,

It is mostly a matter of the direction of heat flow -- warming up or cooling down. When heated, the solid acquires enough energy to collapse into a liquid. When cooled down, the liquid loses enough energy to enable the molecules (sub-units) to form bonds with each other and become a solid. So, the solid collapses to a liquid -- and reforms to a solid at the same energy content.

Regards,
ProfHoff 813



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