Ununoctium
Symbol: Uuo
Atomic Number: 118
Atomic Mass: presumptive 294 amu (atomic mass units)
Melting Point: Unknown
Boiling Point: Unknown
Number of Protons: 118
Number of Electrons: 118
Number of Neutrons: 176
Classification: Noble Gas
Crystal Structure: Unknown
Density @ 293 K: Unknown
Color: Unknown
Ununoctium is a man-made “super-heavy” element. It exists solely within a detection chamber in a laboratory. It is named in accordance with the International Union for Pure and Applied Chemistry (IUPAC) naming system for new elements, un-un-oct means 1-1-8. Its symbol is derived from the initial letters of these syllables: Uuo. “Super heavy” elements are made by bombarding atoms of one element with the ions of another to force them to combine into a new element.
In 1999 scientists at Berkeley Laboratories announced that they had formed the new element ununoctium by bombarding lead-208 with an accelerated beam of krypton-86 ions. In addition to ununoctium they also reported the formation of element 116, ununhexium. However later confirmatory experiments failed to yield the expected results and the team withdrew its claim to the new elements.
A second claim to the new element came from Russia in 2002. Scientists at the Flerov Laboratory of Nuclear Reactions in Dubna, Russia had irradiated a target of Californium-294 atoms with ions of Calcium-48 for one thousand and eighty hours. The result of this was one atom of ununoctium-294 was produced. The atom emitted an alpha particle in 1.29 milliseconds to become ununhexium-290, another alpha particle was emitted and the element became ununquadium-286 with final loss of another alpha particle ununbium-282 was formed 280 milliseconds later. This work was carried out by two teams of scientists working at the laboratory one from the Joint Institute for Nuclear Research in Russia and the other from the Lawrence Livermore National Laboratory in the USA. Unlike the Berkeley claim this one was substantiated when a further two atoms of the element were produced by these teams in 2005.
With such a small number of short lived atoms produced very little about the properties of ununoctium. At present only one isotope of ununoctium has been found, ununoctium-294, it is radioactive and has a half life estimated at 0.89 milliseconds. Ununoctium is the element at position118 in the periodic table. This position puts ununoctium in group eighteen, period seven and in p-block of the elements. It is in the same group as the noble gases such as neon, krypton and xenon. From this is has been deduced that it would be a colorless, odorless gas at room temperature.
