Transport phenomena delve into the movement of mass, momentum, and energy, guiding the design of reactors, separators, and heat exchangers. Reaction engineering elucidates the kinetics and mechanisms of chemical reactions, essential for reactor design and catalyst development. Additionally, process control theory provides tools for maintaining and optimizing process performance, ensuring safety and efficiency in industrial operations. These theories collectively underpin the diverse facets of chemical engineering, facilitating the design and operation of processes across various industries, from pharmaceuticals to petrochemicals.