1. 13.1 A Model to Explain Gas Behavior

2. The Nature of Gases Air is a mixture of gases
Gases will occupy the volume available to them
Gases can be compressed
Regardless of their identity, all gases exhibit remarkably similar physical behavior
At 0 C° and 1 atm pressure, one mole any gas will occupy 22.4 L.

3. Physical Properties of all Gases
Gases have mass.
It is easy to compress gases.
Gases fill their container completely.
Different gases can move through each other rapidly (diffusion).
Gases exert pressure.
The pressure of a gas depends on its temperature.

4. Kinetic-Molecular Theory
A gas consists of very small particles, each of which has a mass.
The distance separating particles in a gas is very large, therefore the volume the actual particles occupy is negligible.
Gas particles are in constant rapid, random motion.

5. Kinetic-Molecular Theory
Collision between gas particles or between a gas particle and the container are elastic.
Temperature depends on average kinetic energy.
Gas particles exert no attractive forces between themselves.