Ununpentium

General properties
Name, symbol, number	ununpentium, Uup, 115
Element category	unknown
Group, period, block	15, 7, p
Standard atomic weight	(288)
Electron configuration	[Rn] 5f14 6d10 7s2 7p3 (predicted) 2, 8, 18, 32, 32, 18, 5 (predicted)
History
Discovery	Joint Institute for Nuclear Research and Lawrence Livermore National Laboratory (2003)

Ununpentium is the temporary name of a synthetic superheavy element in the periodic table that has the temporary symbol Uup and has the atomic number 115.

It is placed as the heaviest member of group 15 (VA) although a sufficiently stable isotope is not known at this time that would allow chemical experiments to confirm its position as a heavier homologue to bismuth. It was first observed in 2003 and about 50 atoms of ununpentium have been synthesized to date, with about 25 direct decays of the parent element having been detected. Four consecutive isotopes are currently known, ^287–290Uup, with ²⁸⁹Uup having the longest measured half-life of ~200 ms.

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