Hi Eric,
The Kinetic-Molecular (K-M) Theory assumes a sample consisting of a large
number of gas phase particles with an average kinetic energy that is
proportional to the sample's absolute temperature. The particles are in
continuous, random motion with an average kinetic energy that does not
change as long as the temperature remains constant. No particles or energy
are gained or lost by the sample.
Each particle in this sample is moving independently of all other particles
and energy can be transferred between particles during collisions but all
collisions are perfectly elastic. At any moment in time, some of the
particles are moving very rapidly and some are moving very slowly. The
fraction of the sample moving at any chosen velocity changes with
temperature. It was long ago demonstrated that the actual distribution of
particle energy (velocity) follows a Boltzmann Distribution. The nature of
a Boltzmann Distribution is responsible for the differences in the peak
positions and widths of the curves shown in the
referenced
graphs.
Additional information, discovered using an internet search engine, can be
found at:
Kinetic Molecular
Theory - and links therein
The
Kinetic Molecular Theory
Kinetic
Theory - and links therein
for example:
Physical
Applications of Distribution Functions
Maxwell-Boltzmann
Distribution
Maxwell
Speed Distribution
John Haberman
Try the links in the MadSci Library for more information on Chemistry.