IG Phy – States of Matter and Molecular Model

A solid has a fixed volume and shape, is not easily compressed, and does not flow easily.

A liquid assumes the shape of its container, is not easily compressed, and flows easily.

A gas has a fixed shape and volume, and is not easily compressed.

The process of a solid changing to a liquid is called evaporation.

The process of a liquid changing to a gas is called condensation.

The process of a gas changing to a liquid is called condensation.

The particles in a solid are completely still and do not move.

When the temperature of a solid is increased, its particles vibrate more and move further apart.

The volume of a liquid is fixed and does not change.

Gases have particles that are closely packed and move past each other easily.

The kinetic particle model explains that the particles in a gas move faster at higher temperatures.

Gases exert pressure because their particles collide with the walls of the container.

A helium atom is an example of a molecule.

Water molecules consist of two hydrogen atoms and one oxygen atom.

As the temperature of a gas decreases, the speed of its molecules increases.