The proposed material covers the sections on chemical equilibrium and properties of solutions and contains updated information on the following areas:homogeneous chemical equilibrium (in gas and liquid phase); heterogeneous chemical equilibrium in systems: liquid-solid, solid-gas, liquid-liquid; solubility of inorganic substances in aqueous, non-aqueous and mixed media; azeotropic solutions (both "true" azeotropes with one liquid phase and heteroazeotropes, of which the composition of the vapor is in equilibrium with the delaminating solution at boiling point).