111 Rg 282

Roentgenium

unknown, probably transition metal

Properties

Atomic number
111
Atomic mass
282 u
Category
unknown, probably transition metal
Group
11
Period
7
Block
d-block
State (room temp)
Solid
Outer-shell electrons
2
Electronegativity
-
Density
28.7 g/cm³
Melting point
-
Boiling point
-

Electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴ 6d⁹

Noble-gas shorthand: [Rn] 5f¹⁴ 6d⁹ 7s²

Electrons per shell: 2, 8, 18, 32, 32, 17, 2, which is 2 in the outermost shell.

Related: electron configuration, the Bohr model, valence electrons.

Rg
Bohr model; outer-shell electrons in blue

About Roentgenium

Roentgenium is a chemical element with symbol Rg and atomic number 111. It is an extremely radioactive synthetic element (an element that can be created in a laboratory but is not found in nature); the most stable known isotope, roentgenium-282, has a half-life of 2.1 minutes. Roentgenium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany.

Roentgenium: frequently asked questions

What is Roentgenium?
Roentgenium (Rg) is the chemical element with atomic number 111. It is not yet firmly classified; it is listed as "unknown, probably transition metal".
What is the atomic number of Roentgenium?
Roentgenium's atomic number is 111, which means every Roentgenium atom has 111 protons in its nucleus.
What is the electron configuration of Roentgenium?
The electron configuration of Roentgenium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d9 (noble-gas shorthand: [Rn] 5f14 6d9 7s2). Its electrons are arranged in shells of 2, 8, 18, 32, 32, 17, 2, with 2 in the outermost shell.
Is Roentgenium a metal or a nonmetal?
Roentgenium is not yet firmly classified; it is listed as "unknown, probably transition metal".
What group and period is Roentgenium in?
Roentgenium is in group 11 and period 7 of the periodic table.
Is Roentgenium a solid, liquid, or gas?
At room temperature, Roentgenium is a solid.

Position in the periodic table

Open the interactive periodic table →

Data compiled from Wikipedia, PubChem, and IUPAC. Source.