roentgenium

Also known as Rg, element 111, Uuu, unununium, ununnilium

Roentgenium () is a synthetic chemical element; it has symbol Rg and atomic number 111. It is extremely radioactive and can only be created in a laboratory. The most stable known isotope, roentgenium-282, has a half-life of 130 seconds, although the unconfirmed roentgenium-286 may have a longer half-life of about 10.7 minutes. Roentgenium was first created in December 1994 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany. It is named after the physicist Wilhelm Röntgen (also spelled Roentgen), who discovered X-rays. Only a few roentgenium atoms have ever been syn

AI overview

Roentgenium is a human-made chemical element (symbol Rg, atomic number 111) that is extremely radioactive and breaks down so quickly that it can only exist in laboratory conditions. Named after X-ray discoverer Wilhelm Röntgen, it was first created in 1994 and remains scientifically significant primarily as a product of heavy-ion physics research rather than for any practical applications.

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Wikidata facts

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element symbol: Uuu
Commons category: Roentgenium
time of discovery or invention: 1994-12-08
atomic number: 111
Commons gallery: Roentgenium
Unicode character: 𬬭

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Article

15 sections

Contents

Introduction
History
Official discovery
Naming
Isotopes
Stability and half-lives
Predicted properties
Chemical
Physical and atomic
Experimental chemistry
See also
Explanatory notes
References
General bibliography
External links

In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and is placed in the group 11 elements, although no chemical experiments have been carried out to confirm that it behaves as the heavier homologue to gold in group 11 as the ninth member of the 6d series of transition metals. Roentgenium is calculated to have similar properties to its lighter homologues, copper, silver, and gold, although it may show some differences from them.