Behavior of Gases-Kinetic Molecular Theory

Gases behave very differently from solids and liquids. The behavior of gases can be explained by kinetic molecular theory (KMT). An ideal gas is a gas that obeys 5 postulates of KMT.

  • Gas particles are very small - so small that we can count their volume as zero. A gas is mostly just empty space
  • Gas particles are in contant random straight-line motion, obeying Newton's laws, and only changing direction when they impact other particles or the walls of their containers.
  • Collisions between gas particles are perfectly elastic, meaning that no kinetic energy is lost in those collisions.
  • Gas paricles do not interact with each other except when they collide. There are no attractive or repulsive forces between them.
  • The temperature of a gas is directly related to the average kinetic energy of the gas particles. As the particles speed up, the average kinetic energy increases as does the temperature.

Practice Worksheets, PowerPoints & Videos

Intro To Gas Laws Worksheet (and the KEY)

PhET Simulation about gas molecules (requires Java)

Gas Properties
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The practice workshsheets above are original and have keys available. Also available are links to resources on other sites, including simulations and videos produced by others
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