Chemistry of positronium

The material illustrating general approach to investigations in the field of new atoms chemistry is presented in the review. Production conditions, positronium atom properties, chemical reactions with its participation, experimental technique in positronium chemistry are considered. Possibilities of positron method for studying physicochemical properties of surrounding positronium medium by examples of investigating the structure and oxidation kinetics of multiphase polymer systems, specific character of heterogeneous catalists effect, determining kine-- tic constants of elementary radiation-chemical processes are shown