Element 111
Roentgenium
Transition metals
Roentgenium (Rg) is in the d-block of the periodic table — group 11, period 7.
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
Periodic table block
Roentgenium is in the d-block (group 11, period 7). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.
New to this? Periodic table blocks explained: s, p, d, and f
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 block of the periodic table is Roentgenium in?
Roentgenium is in the d-block (group 11, period 7). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, *[Rn] 5f14 6d10 7s1.
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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