William D. Scott
Division of Environmental Sciences
Murdoch University
Perth, Western Australia 6150
The power of Maple is apparent when tackling the solution of multivariate
polynominals. Here the equilibrium chemistry of raindrops is considered, in
examples with three levels of complexity. Considered first is the simplest
case of ionic equilibrium with a single solute species derived from Carbon
Dioxide ( 
). Then, the case of species generated from three interacting
sources, including Sulfur Dioxide ( 
) and Ammonia ( 
). Lastly,
chemical kinetics are included with oxidation to sulfate ion. The results
are all applicable to the problem of acid rain, resulting from excess
sulfurous emissions and carbon dioxide. With effort from the user, many more
interactive species may be included, even organics and solids. Maple can
solve these problems, provided the user evolves an appropriate structure.
These three specific cases are important not only in cloud and rain physics and air pollution but also in all our waterways, in our soils and in our foods. The technique is presented as a series of examples. Each uses three types of conditions; 'equilibrium mass action constants', 'mass balances' and a single electroneutrality equation.