a radioactive metallic element that is similar to tellurium and bismuth; occurs in uranium ores but can be produced by bombarding bismuth with neutrons in a nuclear reactor
Polonium. A radioactive element that is a member of the chalcogen family. It has the atomic symbol Po, atomic number 84, and the atomic weight of the isotope with the longest half-life (209Po) is 208.98. It decays by alpha-emission.
A radioactive substance or element, isolated from pitchblende; it is one of the disintegration products of radium emanation; called also radiotellurium.