Thermodynamics: Entropy and Spontaneity in Reactions

This lecture covers fundamental concepts in thermodynamics, focusing on entropy and its implications for chemical reactions. It begins with definitions of entropy, explaining how it relates to the number of microscopic states in a system. The instructor discusses the first and second laws of thermodynamics, emphasizing that spontaneous processes lead to an increase in the total entropy of the universe. The lecture also introduces standard entropy changes for reactions and provides examples, including calculations for specific reactions. The concept of Gibbs free energy is explored, detailing how it can predict the spontaneity of reactions under standard conditions. The relationship between Gibbs energy, enthalpy, and entropy is clarified, along with the effects of temperature on spontaneity. The lecture concludes with a discussion on chemical equilibrium, including the equilibrium constant and its dependence on Gibbs energy. Overall, the lecture provides a comprehensive overview of thermodynamic principles essential for understanding chemical processes.