Diffusion

In the last chapter we examined how to use the kinetics of reactions to model the rate of change of populations, or concentrations. We did not consider the consequences of the motion or spatial transport of these populations. There are multiple mechanisms involved with transport, and in this chapter we will examine one of them, and it is the process of diffusion. A simple example of diffusion arises when a perfume bottle is opened. Assuming the air is still, the perfume molecules move through the air because of molecular diffusion.