Is the total kinetic and potential energy of all the particles in an object or substance.

​​Thermal Energy

Is a measure of the average kinetic energy of the particles in an object or substance.

​​Temperature

Particles have both kinetic energy and potential energy. Kinetic energy is energy of motion, and potential energy is energy that is stored.

When the temperature of most solids increases enough, the solids change to liquid. The change in state from a solid to a liquid is called melting.

MELTING

The temperature at which a substance changes from a solid to a liquid; the same as the freezing point, or temperature at which a liquid changes to a solid.

MELTING POINT

Is the change of state from a liquid to a solid. It is the reverse of melting. Unlike water, some substances do not have to be cold to the touch in order to freeze.

FREEZE

The temperature at which a liquid freezes.

FREEZING POINT