The chemistry of elements of group 17 of the Periodic Table of D. I. Mendeleev is systematically described. In the process, the authors summarized the material contained in the educational and scientific literature, in many cases relying on original research presented in scientific periodicals and not yet included in educational publications. Intended for students in the magistracy in the direction of "Chemistry," however, the material is presented in such a way that it can be useful for first-year students in the process of in-depth study of general and inorganic chemistry. The presented material can be used to study the course "Chemistry of coordination compounds."