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Oganesson (Og)

Oganesson is a chemical element of the periodic table with chemical symbol Og and atomic number 118 with an atomic weight of 294 u and is classed as unknown and is part of group 18 (noble gases). Oganesson is solid at room temperature.

Oganesson in the periodic table

Atomic number118
Group18 (Noble gases)
Number of protons118 p+
Number of neutrons176 n0
Number of electrons118 e-
From Wikipedia, the free encyclopediaOganesson is IUPAC's name for the transactinide element with the atomic number 118 and element symbol Og. It is also known as eka-radon or element 118, and on the periodic table of the elements it is a p-block element and the last one of the 7th period. Oganesson is currently the only synthetic member of group 18.

Physical properties

Phase at STPSolid
Density4.95 g/cm3
Atomic weight294 u

Thermal properties

Melting point-
Boiling point350 K
76.85 °C
170.33 °F
Heat of vaporization-

Atomic properties

Electronegativity (Pauling Scale)-
Electron affinity5.40318 kJ/mol
Oxidation states−1), (0), (+1), (+2), (+4), (+6)
Ionization energies
  1. 860.1 kJ/mol
  2. 1560 kJ/mol

Electron configuration for oganesson

Electron configuration
Shorthand configuration
[Rn] 5f14 6d10 7s2 7p6
Electron configuration
Full configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f14 6s2 6p6 6d10 7s2 7p6
Electron configuration chart
Electrons per shell2, 8, 18, 32, 32, 18, 8
Valence electrons
Valency electrons
Bohr model
OganessonElectron shell for Oganesson, created by Injosoft ABOg
Figure: Shell diagram of Oganesson (Og) atom.
Orbital Diagram

The history of Oganesson

DiscoveryJoint Institute for Nuclear Research, Lawrence Livermore National Laboratory (2002)
Discovery of oganesson
It was first synthesized in 2002 at the Joint Institute for Nuclear Research (JINR) in Dubna, near Moscow, Russia, by a joint team of Russian and American scientists. In December 2015, it was recognized as one of four new elements by the Joint Working Party of the international scientific bodies IUPAC and IUPAP. It was formally named on 28 November 2016.[14][15] The name honors the nuclear physicist Yuri Oganessian, who played a leading role in the discovery of the heaviest elements in the periodic table. It is one of only two elements named after a person who was alive at the time of naming, the other being seaborgium, and the only element whose eponym is alive today.


List of unique identifiers for Oganesson in various chemical registry databases
CAS Number54144-19-3
ChemSpider ID-
EC number-
PubChem CID Number-