Flerovium | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Pronunciation | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Mass number | [289] (unconfirmed: 290) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Flerovium in the periodic table | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Atomic number (Z) | 114 | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Group | group 14 (carbon group) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Period | period 7 | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Block | p-block | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Electron configuration | [Rn] 5f14 6d10 7s2 7p2 (predicted)[3] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Electrons per shell | 2, 8, 18, 32, 32, 18, 4 (predicted) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Physical properties | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Phase at STP | liquid (predicted)[4] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Melting point | 284 ± 50 K (11 ± 50 °C, 52 ± 90 °F) (predicted)[4] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Density (near r.t.) | 11.4 ± 0.3 g/cm3 (predicted)[4] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Heat of vaporization | 38 kJ/mol (predicted)[5] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Atomic properties | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Oxidation states | common: (none) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Ionization energies | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Atomic radius | empirical: 180 pm (predicted)[3][5] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Covalent radius | 171–177 pm (extrapolated)[7] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Other properties | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Natural occurrence | synthetic | |||||||||||||||||||||||||||||||||||||||||||||||||||||
CAS Number | 54085-16-4 | |||||||||||||||||||||||||||||||||||||||||||||||||||||
History | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Naming | after Joint Institute for Nuclear Research (itself named after Georgy Flyorov)[8] | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Discovery | Joint Institute for Nuclear Research (JINR) and Lawrence Livermore National Laboratory (LLNL) (1999) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
Isotopes of flerovium | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Flerovium is a synthetic chemical element; it has symbol Fl and atomic number 114. It is an extremely radioactive, superheavy element, named after the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research in Dubna, Russia, where the element was discovered in 1999. The lab's name, in turn, honours Russian physicist Georgy Flyorov (Флёров in Cyrillic, hence the transliteration of "yo" to "e").[16] IUPAC adopted the name on 30 May 2012. The name and symbol had previously been proposed for element 102 (nobelium), but was not accepted by IUPAC at that time.
It is a transactinide in the p-block of the periodic table. It is in period 7, the heaviest known member of the carbon group, and the last element whose chemistry has been investigated. Initial chemical studies in 2007–2008 indicated that flerovium was unexpectedly volatile for a group 14 element.[17] More recent results show that flerovium's reaction with gold is similar to that of copernicium, showing it is very volatile and may even be gaseous at standard temperature and pressure, that it would show metallic properties, consistent with being the heavier homologue of lead, and that it would be the least reactive metal in group 14. Whether flerovium behaves more like a metal or a noble gas is still unresolved as of 2024; it might also be a semiconductor.
Very little is known about flerovium, as it can only be produced one atom at a time, either through direct synthesis or through radioactive decay of even heavier elements, and all known isotopes are short-lived. Six isotopes of flerovium are known, ranging in mass number between 284 and 289; the most stable of these, 289Fl, has a half-life of ~2.1 seconds, but the unconfirmed 290Fl may have a longer half-life of 19 seconds, which would be one of the longest half-lives of any nuclide in these farthest reaches of the periodic table. Flerovium is predicted to be near the centre of the theorized island of stability, and it is expected that heavier flerovium isotopes, especially the possibly magic 298Fl, may have even longer half-lives.
2009ex
was invoked but never defined (see the help page).