Tuesday, August 14, 2007

Ununquadium

Ununquadium
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114 ununtrium ← ununquadium → ununpentium
Pb

Uuq

(Uhq)
Periodic Table - Extended Periodic Table


General
Name, Symbol, Number ununquadium, Uuq, 114
Chemical series presumably poor metals
Group, Period, Block 14, 7, p
Appearance unknown, probably silvery
white or metallic gray
Standard atomic weight (298)  g·mol−1
Electron configuration perhaps [Rn] 5f14 6d10 7s2 7p2
(guess based on lead)
Electrons per shell 2, 8, 18, 32, 32, 18, 4
Phase presumably a solid
CAS registry number 54085-16-4
Selected isotopes
Main article: Isotopes of ununquadium iso NA half-life DM DE (MeV) DP
288Uuq syn 2.8 s

References
Ununquadium (IPA: /ˌjuːˌnʌnˈkwɒdiəm/), or eka-lead, is the temporary name of a radioactive chemical element in the periodic table that has the temporary symbol Uuq and has the atomic number 114.

Contents [hide]
1 History
2 Synthesis
2.1 Synthesis of Ununquadium-298
3 (more) Stable ununquadium
4 See also
5 References
6 External links



[edit] History
The discovery of ununquadium in December 1998 was reported in January 1999 by scientists at Dubna (Joint Institute for Nuclear Research) in Russia.[1] The same team produced another isotope of Uuq three months later[2] and confirmed the synthesis in 2004 and 2006.

In 2004 in the Joint Institute for Nuclear Research the synthesis of this element was confirmed by another method (the chemical identifying on final products of decay of element).

Ununquadium is a temporary IUPAC systematic element name. Some have termed it eka-lead, as its properties are conjectured to be similar to those of lead. It is expected to be a soft, dense metal that tarnishes in air, with a melting point around 200 degrees Celsius.


[edit] Synthesis
Ununquadium can be synthesized by bombarding plutonium-244 targets with calcium-48 heavy ion beams.


[edit] Synthesis of Ununquadium-298
Manufacturing ununquadium-298 would be very difficult, because nuclei summing to 114 protons and 184 neutrons are not available in weighable quantities.

However it may be possible to generate ununquadium-298, if nuclear transfer reactions can be achieved.[citation needed] One of these reactions may be



[edit] (more) Stable ununquadium
According to the island of stability theory, some nuclides around the area of 114 protons and 184 neutrons (i.e. isotope Uuq-298) can be expected to be relatively stable in comparison to the surrounding nuclides. Ununquadium does not occur naturally, so it is entirely synthesized in laboratories. All isotopes of ununquadium synthesized so far are neutron-poor. This means that they contain significantly fewer neutrons than 184, which is one of the magic number of neutrons that is believed to make the isotope more stable. Neutron-poor also indicates that the isotopes decay either by spontaneous fission producing a variety of radionuclides, positron emission or electron capture to yield element ununtrium. So far, all three that have been made so far have achieved spontanious fission in the first .0012 milliseconds, and therefore have never been able to be studied.


[edit] See also
Island of stability: Ununquadium – Unbinilium – Unbihexium
Lead
Periodic table (extended)
Isotopes of ununquadium

[edit] References
^ Oganessian, Yu. Ts.; et al. (October 1999). "Synthesis of Superheavy Nuclei in the 48Ca + 244Pu Reaction". Physical Review Letters 83: 3154. DOI:10.1103/PhysRevLett.83.3154.
^ Oganessian; et al. (July 1999). "Synthesis of nuclei of the superheavy element 114 in reactions induced by 48Ca". Nature 400: 242. DOI:10.1038/22281.

[edit] External links
Wikimedia Commons has media related to:
UnunquadiumWebElements.com - Uuq
Apsidium - Ununquadium
First postcard from the island of nuclear stability
Second postcard from the island of stability
Retrieved from "http://en.wikipedia.org/wiki/Ununquadium"
Categories: All articles with unsourced statements | Articles with unsourced statements since February 2007 | Chemical elements | Poor metals | Nuclear physics

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