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kinetic theory of gases




A mathematical explanation of the behavior of gases based on the model that gases consist of molecules (or atoms) in constant motion in space, the kinetic energy of the molecules depending on the temperature of the gas. The kinetic theory makes seven assumptions:
  1. The volume occupied by the gas molecules themselves is negligible compared with the volume of space between them.
  2. All the particles that make up the gas are identical.
  3. The distribution of energy amoung particles is random.
  4. There are sufficent numbers of molecules for the statistical average to be meaningful.
  5. Collisions are all perfectly elastic.
  6. The molecules travel in straight lines between collisions.
  7. Newtonian mechanics can be applied to molecule interactions.
The pressure exerted by a gas on the walls of the vessel is due to the collision of the molecules with it. The gas laws may be shown to be in full agreement with this theory.


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   • HEAT AND THERMODYNAMICS
   • PHYSICAL CHEMISTRY