Ununhexium
Symbol: Uuh
Atomic Number: 116
Atomic Mass: 291 (atomic mass units)
Melting Point: Unknown
Boiling Point: Unknown
Number of Protons: 116
Number of Electrons: 116
Number of Neutrons: 176
Classification: Metal (man made)
Crystal Structure: Unknown
Density @ 293 K: Unknown
Color: Unknown
Ununhexium is a man-made, radioactive, super-heavy element. It was produced by an international team of scientists from three laboratories within the Russian Federation; The Joint Institute for Nuclear Research, Dubna; The Research Institute of Atomic Reactors; Dimitrovgrad; The State Enterprise Electrohimpribor, Lesnoy, along with workers from The Lawrence Livermore National Laboratory, California, USA. The results of their experiments were published on the 6th December 2000. Using the International Union of Pure and Applied Chemistry (IUPAC) naming system for new elements their discovery was given the temporary holding name of ununhexium which mean one-one-six and relates to its atomic number. IUPAC has now given this element the provisional name Livermorium in honor of the Lawrence Livermore National Laboratory.
Like all of the super-heavy elements ununhexium was produced by accelerating ions of one element and aiming them at a target made of atoms of another. This collision forces the two elements to combine to form a new element. In the case of ununhexium, ions of calcium-48 were used to bombard a target made of curium-248 atoms. This collision produced the isotope ununhexium-292 with the release of four free neutrons. The isotope ununhexium-292 has a half life of about 0.6 milliseconds and decays, by alpha decay mode, to form an isotope of another already known super-heavy element, ununquadium-288.
Two other isotopes of ununhexium have since been produced. Ununhexium-291 has the longest half life at 18 milliseconds while ununhexium-290 has a half life of 7.1 milliseconds. Both of these isotopes decay by alpha decay mode to form different isotopes of ununquadium.
To date none of the bulk properties, such as density or boiling and melting points, of ununhexium have been able to be measured. This is because so few atoms of this element have been produced and those that have been made have very short half lives. Its position in group 16, also known as the chalcogen group, of the periodic table puts it in the same group as the elements oxygen, sulphur, selenium, tellurium and polonium. It has been deduced that it is a metal and is probably silvery white or gray in color.
Ununhexium obviously has no current industrial uses and it is unlikely to ever have such uses. The element remains of scientific interest and is studied by groups researching the super-heavy elements.
