The book discusses the basic concepts and laws of chemistry: the structure of matter, chemical bonding (the method of molecular orbitals, the method of valence bonds, the zone theory of crystals), the most important provisions of chemical thermodynamics and chemical kinetics, methods for studying the structure of substances. The chemistry of the elements is presented on the basis of the periodic law of D.I. Mendeleev with the involvement of structural and thermodynamic representations. The textbook is intended for students of areas of training and specialties included in the UGSN: "Chemistry," "Biological Sciences," "Chemical Technologies," "Industrial Ecology and Biotechnology," as well as for graduate students and teachers of chemical faculties of universities and chemical-technological universities.