unit process

A unit process is a chemical change that occurs as a step in a manufacturing process. These changes involve the rearrangement of atoms to form new substances, distinguishing them from physical changes where the chemical identity remains the same. Chemical engineering, which applies principles of chemistry, physics, and mathematics, is concerned with developing processes and designing plants where these chemical changes occur.123

Unit processes can be classified into groups with common characteristics, such as esterification or nitration, which helps rationalize the study of process engineering. These processes are fundamental to the construction of complex chemical compounds from simpler ones, a process known as chemical synthesis.34