Teaching Light Scattering to Reinforce Basic Principles

The fundamental equations used in the static light scattering analysis of polymer solutions are introduced with explanation of their foundation in thermodynamics. A simple link between the ideal gas law, osmotic pressure, and the static light scattering technique is developed, showing how concepts introduced in freshman chemistry for gases and reinforced in physical chemistry for solutions of small molecules can be extended naturally to a difficult problem of enormous practical importance: the characterization of large, macromolecular chains. Other important concepts, such as wave interference, spatial frequency, and stratagems for handling data are also discussed in the context of the static light scattering experiment.