Temperature, Heat and Matter

Thermal expansion:

The expansion of matter when its temperature is raised.

Pressure: 

The force on each unit of area of a surface.

melting:

The change of a solid into a liquid.

vaporization:

The change of a liquid to a gas as molecules break free from each other.

Condensation:

The change of a gas into a liquid as molecules attract each other.

freezing: 

The change of a liquid into a solid.

boiling:

the formation of bubbles of vapor that scape from a liquid that is being heated.

evaporation: 

the vaporation of molecules from the surface of a liquid.