Chapter 27 Kinetic Theory of Gases
In the last few chapters you have studied laws of thermodynamics. You may have noticed that in thermodynamics we study properties of equilibrium states of macroscopic systems. Thermodynamics does not give us detailed information about the microscopic origins of the macroscopic properties. For instance, thermodynamics does not tell us about the physical basis of a particular gas pressure, although pressure of a gas must be the result of impulses on the walls of the container from the moving gas molecules.
The shortcomings of the equilibrium thermodynamics, stated above, are addressed by introducing microscopic pictures or models of materials in terms of their atomic and molecular constituents. Basically, there are two approaches for understanding the origins of macroscopic properties based on molecular motion and interactions: statistical mechanics and kinetic theory.
We will not study statistical mechanics here, but rather concentrate on the basic ideas of kinetic theory. Kinetic theory also helps one study nonequilibrium properties from a fundamental molecular viewpoint. To begin our discussion of kinetic theory, we will start with the study of the simplest system, the ideal gas.
