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 — that's 2 in the outermost shell.

See how electron configuration is built →

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.

Position in the periodic table

Open the interactive periodic table →

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