- Gases consist of particles (atoms or molecules) that are in constant random motions
- Gas particles are constantly colliding with each other and the walls of their container
- 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
- 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 →