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Elements, Compounds and Mixtures
Solid, Liquid and Gas - Melting and Boiling.
The graph
below shows how the temperature
changes with time
as a substance is heated at a constant
rate.
There are obvious flat sections of the
graph at the melting and boiling point.
At the melting point, although the substance is still being heated,
there is a time when the temperature does not
change.
During this time, all the extra heat
which is being added
goes to overcome the force of attraction
(the bonds)
between the particles of the
solid as it turns into a liquid.
The temperature of a solid can never be
raised
above its melting point at
atmospheric pressure.
When all the solid has melted,
then the temperature of the
liquid will start to rise
(continued on the next page).
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Copyright © 2008 Dr. Colin France. All Rights Reserved.
