The kinetic molecular theory allows us to explain behavior of gases through modeling.
Assumptions of the kinetic molecular theory:
- Particles of the gas are small and have negligible volume compared to the size of the container. Therefore, most of the container is empty space and the space between the particles allows the volume of the gas to be compressed.
- Particles have high kinetic energy and are in constant, random, straight line motion. Particles experience elastic collisions with each other and with the sides of the container creating pressure.
- Particles do not attract or repel one another.
- Particles have an average kinetic energy directly related to Kelvin temperature. (ie. Particles move faster as temperature increases.)
Real gases vs. Ideal Gases: Ideal gases follow all assumptions of the kinetic molecular theory;however, particles in a real gas do have their own volume and experience attractions. Gas behavior is most ideal at low pressure, high temperature, and in nonpolar molecules.