Modern chemistry is essentially pictorial. Most of our success in explaining how chemical reactions take place has come from a knowledge of the structures of molecules in three dimensions, and the arrangements of electrons in molecules. Although the calculations of modern theoretical chemistry can be complicated, they are based firmly on models of molecules and reactions. The chemist combines information from many sources, and uses his imagination to "see" molecules that are below the resolving power of the finest microscope.

A one-line chemical equation can conjure up images of moving and colliding molecules in the mind of the experienced chemist, but to a beginner it can conceal as much as it reveals. An introductory chemistry textbook should illustrate in clear detail exactly what these shorthand equations really symbolize. At the beginning level, the guiding principle should be, "When in doubt, draw it out." An ideal combination of authors would be a chemist who understands the art of graphic presentation, and an illustrator who understands chemistry. This is the combination we have tried to put together in this book.