Thermodynamics — First Law and Thermochemistry

First law of thermodynamics at PGT depth: system/surroundings/boundary, state vs path functions, internal energy, heat and work sign conventions, enthalpy, Hess's law, Kirchhoff's equation, bond energies, heat capacities, reversible/irreversible processes, isothermal and adiabatic work, Joule–Thomson effect, and calorimetry.