Lesson 7: Just A Phase

Key Terms

SolidA solid has definite volume and

definite shape.

The particles in a solid are closely packed and vibrate in relation to one

another.

LiquidA liquid has definite volume, but no definite shape. A liquid takes on the

shape of its container.

GasA gas has no definite shape or

volume. Its particles have enough energy to fill the entire container it

is in.

The Phases of Matter

MeltingChanging from a Solid to a

Liquid

Freezing

Changing from a liquid to a solid

Boiling

Changing from a liquid to a gas at a substance’s boiling point.

Also called vaporization

EvaporatingChanging from a liquid to a gas at the

surface of a liquid.

Condensing

Changing from a gas to a liquid

Due to a change in temperature

Latent Heat of Fusion

The heat absorbed when a solid turns into a liquid

Latent Heat of Vaporization

The heat absorbed when a liquid turns into a gas.