Thus far we have mentioned the term model a number of times, and you probably have a vague notion of what we mean by model. The following definition of a model is from the McGraw-Hill Dictionary of Scientific and Technical Terms:
“A mathematical or physical system, obeying certain specified conditions, whose behavior is used to understand a physical, biological, or social system to which it is analogous in some way.”
In this textbook, model will be taken to mean mathematical model. More specifically, we develop process models. A working definition of process model is
a set of equations (including the necessary input data to solve the equations) that allows us to predict the behavior of a chemical process. ...