Krypton (Krypton, Kr) is a chemical element zero of the group of the periodic system D. I. Mendeleev, number 36, atomic weight 83,80. In nature, occurs only in the idle state. In the atmospheric air contains 0,0003% by weight. Monatomic gas. Chemically inactive. Krypton is produced during the distillation of liquid air. For radiocative used Kr86 (see Radioisotope diagnostics).