1. Gases consist of particles (atoms or molecules) that are in constant random motions
  2. Gas particles are constantly colliding with each other and the walls of their container
  3. There are no interactive forces (attraction or repulsion) between the particles of a gas
  • Collisions between gasses is elastic: no effect and KE is conserved

         ○ For real gasses: between collisions, particles have constant velocity and direction which change after collisions

  1. The avg kinetic energy of gas particles only depends on the absolute temperature of the gas → all gases at the same temperature have the same avg kinetic energy
  •  But the speed of the particles is affected by both temperature and the molar mass of the gas

           ○ Smaller particles travel at faster speeds than heavier/larger gases.

Maxwell-Boltzmann Practice

  • A Maxwell-Boltzmann distribution show the relationship between temperature and average KE
  • Lower temp → peak more to the left, higher, extends below Ea

          ○ Heavier gasses will have curve like the lower temp one

Characteristics of an Ideal Gas:

    • The particles of ideal gases do not have volume, pressure, or forces
    • All types of gases have the same [partial] pressure at constant conditions

Real Gas Behavior

  • The particles of real gases have volume, pressure, and InterMFs                                                         
  • Their particles vary in size, are all able to condense, and have a variety of speeds
  • Speed of a gas at a fixed temp