INORGANIC CHEMISTRY A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site polonium (Po) Polonium atom. Source: Wikipedia A soft, gray, radioactive, metallic element of group VIA of the periodic table, discovered in 1898 by Marie Curie. It is found in trace amounts in uranium ores and may also be synthesized by neutron bombardment of bismuth. The commonest isotope, 210Po, emits alpha particles (half-life 138.4 days), and is used in neutron sources; the most stable isotope is 209Po. atomic number 84 relative density 9.40 melting point 254°C (489°F) boiling point 962°C (1,764°F) Related category    • INORGANIC CHEMISTRY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP