Polonium, including Technical Data, Safety Data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure,ionization energy, abundance on Earth, conductivity and thermal properties are included.
Polonium is a highly reactive silver-gray metal that is very soluble in acid and mildly soluble in alkalis. It is the only metallic element that exits in a simple cubic array with six bonds per atom. Many of its industrial applications involve the ability of the Polonium 210 Isotope to electrically charge ambient air. Statically charged dust particles are neutralized making them easier to remove. This has resulted in uses for Polonium 210, including as anti-static brushes and anti-static fans which can remove fine dust particulate from optical lenses, advanced laboratory weighing equipment, photographic film and in metal rolling and textile mills and in clean room environments. It is used in research as a source of Alfa radiation and has been alloyed with other metals, such as Beryllium, to produce a transferable neutron source. Polonium and its isotopes, such as Polonium 210, is a strong radioactive alpha emitter with no stable isotopes. American Elements therefore does not sell Polonium products. The AE IsotopeT product group contains only non-radioactive (stable) isotopes. Information, applications and properties for Polonium are provided.
In November 2006, it was used as an apparent assassination tool in the poisoning of Alexander Litvinenko, a Russian dissident and former KGB agent. Previously, Polonium was used in the space programs of both the United States and the Soviet Union. The United States tested it as a thermoelectric power source for satellites. 140 watts of power can be produced per gram of Polonium 210. The U.S.S.R briefly used Polonium to provide heating to its Lunokhod moon rover. During World War II, it was used in the Manhattan project as a triggering device in the Fat Man atomic bomb dropped on Nagasaki, Japan.
Polonium is a Block P, Group 16, Period 6 element. The number of electrons in each of polonium‘s shells is 2, 8, 18, 32, 18, 6and its electronic configuration is[Xe]6s24f145d106p4. In its elemental formpolonium‘s CAS number is 7440-08-6. The polonium atom has a radius of 168pmand it‘s Van der Waals radius is 197pm. Polonium is both toxic and radioactive.
It was discovered in commercially grown tobacco plants after U.S. tobacco growers began using phosphate fertilizers containing uranium bearing calciumphosphate ores which overtime release radon gas. The radon gas in turn caused other radioactive isotopes of Polonium and Lead to deposit on the leaves. The burning of the leaves in the smoking process causes the highly volatile Polonium 210 Isotope to form a gas. Because Polonium 210 is highly soluble (see above), it can then freely move through the body after ingestion. One Harvard medical study in the 1960‘s claimed that Polonium 210 radioactivity alone was sufficient to make it a contributing cause of lung cancer in smokers. Subsequently, the Surgeon General has said that 90% of tobacco-related lung cancer deaths are a result of radioactivity rather than tar and nicotine poisoning.
Polonium is found in uranium ores. Polonium was first discovered by Madame Marie Curie in 1898 who extracted it from Pitchblende, a then known uranium source. She named it after her birthplace of Poland. Polonium has 12 isotopes. It is now commercially produced by neutron bombardment of bismuth 209 isotopes. Polonium‘s most stable isotope is Polonium 209 with a half life of 102 years. Polonium 210 has a half life of approximately 138.39 days.
Abundance. The following table shows the abundance of polonium and each of its naturally occurringisotopes on Earth along with the atomic mass for each isotope.
The following table shows the abundance of polonium present in the human body and in the universe scaled to parts per billion (ppb) by weight and by atom:
Safety Data and Biological Role. The safety data for polonium metal, nanoparticles and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the left margin. Poloniumcompounds have no biological role. Ionization Energy. The ionization energy for polonium(the least required energy to release a single electron from the atom in it‘s ground state in the gas phase) is stated in the following table:
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Formula | Atomic Number | Molecular Weight | Electronegativity (Pauling) | Density | Melting Point | Boiling Point | Vanderwaals radius | Ionic radius | Energy of first ionization |
Po | 84 | 210 | 2.0 | 9.51 g.cm-3 at 20 °C | 254 °C | 962°C | 0.164 nm | 0.102 nm (+4) | 813.0 kJ.mol-1 |