The scope of thermodynamics. Definitions; the concept of equilibrium. Conventions and mathematical methods. Solutions. The first law of thermodynamics and the concept of energy. The fugacity. Application of the second law to solutions. The perfect solution. The laws of the dilute solution. Systems involving variables other than pressure, temperature and composition. A useful function, called the activity, and its application to solutions. Change of activity with the temperature, and the calculation of activity from freezing points. The standard change of free energy; the equilibrium constant. Solutions of electrolytes. The activity of strong electrolytes. The activity of electrolytes from freezing point data, and tables of activity coefficients. Activity coefficient in mixed electrolytes; the principle of the ionic strength; the activity of individual ions. The galvanic cell. Single potentials; standard electrode potentials of the elements. The third law of thermodynamics. The entropy of monatomic gases and a table of atomic entropies. Introduction to systematic free energy calculations: the free energy of elementary hydrogen and metallic hydrides. Oxygen and its compouns with hydrogen and with some metals. Chlorine and its compouns. Bromine and its compounds. Iodine and its compounds. Nitrogen compounds. Carbon and some of its compounds. Compounds of carbon and nitrogen. Table of free energies; and examples illustrating its use. Conversion table for mol fractions, mol ratios and molities. Some useful numerical factors. Coefficients employed in converting activity, equilibrium constant and free energy from one temperature to another. Publications by the authrs, pertaining to thermodynamics.