Phase Changes

Front

Altitude

Back

Vertical distance, or elevation, above sea level.

Front

Boil

Back

Change from a liquid to a gas.

Front

Boiling point

Back

The temperature at which boiling occurs. At sea level, the boiling point of water is 100 °C (212 °F).

Front

Freeze

Back

Change from a liquid to a solid.

Front

Freezing point

Back

The temperature at which freezing occurs. At sea level, the freezing point of water is 0 °C (32 °F).

Front

Gas

Back

A phase in which matter has no definite shape or volume. Molecules are relatively far apart and move freely.

Front

Liquid

Back

A phase in which matter has definite volume but no definite shape. Molecules move randomly but stay close to one another.

Front

Melt

Back

Change from a solid to a liquid.

Front

Melting point

Back

The temperature at which melting occurs. At sea level, the melting point of ice is 0 °C (32 °F).

Front

Phase

Back

A state of matter with certain physical properties. Solid, liquid, and gas phases occur naturally on Earth.