The combined gas law can be generalized to include the mass of the gas. If the mass of a gas is expressed in moles, the combined gas law can be written as



where R is the universal gas constant, .082 liters × atmospheres/Kelvin Degrees × moles.
The kinetic theory of matter is that matter in all phases consists of tiny particles called molecules which are in motion. The ideal gas law can be derived theoretically by assuming that the forces that exists between the molecules of an idea gas are zero except when the gas molecules collide. When a collision occurs there is no loss of kinetic energy (elastic collision). In this proof, the temperature of an ideal gas is assumed to be directly proportional to the average kinetic energy of the molecules.

  1. Construct a table which shows the relative strength of the attractive forces between molecules, the molecular kinetic energy, and the temperature for the three phases of matter according to the kinetic theory of matter.
  2. Why does the existence of the universal gas constant prove the truth of the kinetic theory of matter.
  3. Why is the product of the pressure and volume of a gas proportional to the average kinetic energy of the gas molecules?
  4. Give an example of an inelastic collision and an elastic collision.
  5. Is momentum conserved in an inelastic collision?