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111Rg282 u

Roentgenium

transition metal
Atomic Number
111
Atomic Mass
282 u
Period
7
Group
11

Quick Facts

PropertyValue
SymbolRg
Atomic Number111
Atomic Mass[282] u
CategoryTransition Metal
Period7
Group11
Blockd
Electron Configuration[Rn] 5f¹⁴ 6d⁹ 7s²

History and Discovery

Discovered by: Sigurd Hofmann and colleagues Year of Discovery: 1994 Location: GSI, Darmstadt, Germany

Etymology

Named after Wilhelm Röntgen, discoverer of X-rays.

Interesting Facts

  1. Named after Wilhelm Röntgen (X-ray discoverer)
  2. Predicted to resemble gold
  3. Most stable isotope has about 2.1-minute half-life
  4. Only a few atoms have been produced
  5. Properties are theoretical predictions