How do chemical engineers apply theoretical principles to optimize processes, design efficient systems, and develop innovative solutions across diverse industries? Explore the foundational theories underpinning chemical engineering, including thermodynamics, kinetics, transport phenomena, and process control. Investigate the role of mathematical modeling and simulation in predicting system behavior and guiding decision$-$making. Delve into theories governing reaction engineering, separation processes, and material properties, and their applications in pharmaceuticals, energy production, environmental remediation, and beyond. How do these theoretical frameworks enable chemical engineers to tackle complex challenges, enhance sustainability, and contribute to advancements in technology and society?