We begin to examine 19th-century physical chemistry with thermodynamics. We hear of Rudolf Clausius and the two Laws of Thermodynamics, as well as entropy. There is Hess's Law, and Berthelot's calorimeter. We hear how Alexander Williamson started the field of chemical kinetics. Waage and Guldberg propose the Law of Mass Action, which tells us what concentrations of chemicals are at equilibrium.Support the show