The microcomputer has put a vast amount of computational power in the hands of the practicing chemical engineer. However, a microcomputer is of little use unless there are programs available to solve chemical engineer­ ing problems; In this book, I have put together a collection of BASIC pro­ grams that w~ll help the practicing engineer be more productive and able to solve complex problems that are normally handled on mainframe com­ puters. The plant engineer will find the book particularly useful. The plant en­ gineer is calle~ upon to investigate problems that range from simple trouble shooting to tQe detailed design of complex chemical plants. The larger proj­ ects are usually add-on jobs to the regular duties of keeping a chemical plant running. In t~day's business climate, answers to problems must be obtained quickly and ~ccurately. The computer is capable of testing hypothesis, thereby allo~ing engineers to evaluate alternative solutions to problems quickly and provide answers to management's questions that invariably shift like the sand~ in a desert.