Chemical Thermodynamics: Principles and Applications

This lecture introduces the fundamental concepts of chemical thermodynamics, focusing on the principles governing energy changes during chemical reactions. It begins with an overview of thermodynamic functions and their variations during reactions, emphasizing the importance of state functions. The instructor explains the first law of thermodynamics, detailing how energy conservation applies to chemical systems. Different types of systems—open, closed, and isolated—are discussed, along with their interactions with the environment. The lecture further explores the concept of enthalpy, including its definition and significance in chemical reactions, particularly at constant pressure. The instructor illustrates endothermic and exothermic processes with examples, highlighting the enthalpy changes associated with phase transitions. The methods for calculating enthalpy changes, such as Hess's law and standard enthalpies of formation, are also covered. The lecture concludes with a discussion on the practical applications of these thermodynamic principles in predicting reaction spontaneity and understanding reaction mechanisms.