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111Rg

Element 111

Roentgenium

Transition metals

Roentgenium is a chemical element with symbol Rg and atomic number 111.

Key data

Atomic number
111
Atomic mass
282.000 u
Group / Period
11 / 7
Block
d-block
Phase at STP
Solid
Density
28.7 g/cm³
Melting point
Boiling point
Electron configuration
*[Rn] 5f14 6d10 7s1

Common uses

  • Research only
  • Named after Wilhelm Röntgen
  • Synthesized 1994

Discovery

Year: 1994

Discovered by: Gesellschaft für Schwerionenforschung

Frequently asked questions

What is the atomic number of Roentgenium?

Roentgenium has atomic number 111. Its symbol is Rg and its atomic mass is 282 u.

What category of element is Roentgenium?

Roentgenium is classified as transition metals. It sits in group 11, period 7 of the periodic table.

What is Roentgenium used for?

Common uses of Roentgenium include: Research only, Named after Wilhelm Röntgen, Synthesized 1994.

When was Roentgenium discovered?

Roentgenium was discovered in 1994 by Gesellschaft für Schwerionenforschung.

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