Roentgenium

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General Properties
Atomic number Predicted atomic mass Half-life of longest living isotope Electron Configuration First developed
111 280amu Around 2 minutes [Rn] 5f14 6d10 7s1 1994
General Properties
Atomic number 111
Atomic mass 280amu
Half-life of longest living isotope Around 2 minutes
Electron Configuration [Rn] 5f14 6d9 7s2
First discovered 1994

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Description and uses

Roentgenium is the 111th element of the periodic table. It was discovered in 1994 by a research team led by Peter Armbruster and Gottfried Münzenberg. Its longest living isotope is 282Rg, with a half life of around 2 minutes.

T&C