Is oganesson a metal?

Oganesson's chemical category has not been confirmed by experiment, so it is listed with unclassified properties.

How many protons does oganesson have?

Oganesson has 118 protons. Its atomic number is 118, which is also the number of electrons in a neutral atom of oganesson.

What group and period is oganesson in?

Oganesson is in group 18 and period 7 of the periodic table, in the p-block.

What is the atomic mass of oganesson?

The atomic mass of oganesson is 294 u (unified atomic mass units).

Element 118

Oganesson (Og)

Element with unclassified properties · Period 7 · Group 18 · p-block

Oganesson (Og) is element 118 of the periodic table, an element with unclassified properties in period 7, group 18 (p-block) with an atomic mass of 294 and is a solid at standard conditions.

At a glance

Atomic number: 118
Symbol: Og
Atomic mass: 294 u
Category: Unclassified properties
Period: 7
Group: 18
Block: p-block
Phase at STP: solid

Electron structure

Electron configuration: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s2 6p6 5f14 6d10 7s2 7p6
Shorthand configuration: [Rn] 5f14 6d10 7s2 7p6
Electrons per shell: 2, 8, 18, 32, 32, 18, 8
Oxidation states: -1, 0, +1, +2, +4, +6

Physical properties

Oganesson has only ever been produced in quantities too small to weigh or observe in bulk. The physical and atomic values below are theoretical predictions from periodic trends and relativistic calculations, not measurements.

Melting point: 325 K (51.85 °C) (predicted)
Boiling point: 450 K (176.85 °C) (predicted)
Density: 5 g/cm³ (predicted)
Phase: solid

Atomic properties

Covalent radius: 157 pm (predicted)
First ionization energy: 839 kJ/mol (predicted)
Electron affinity: 5.4 kJ/mol (predicted)

Notable isotopes

Notable isotopes of Oganesson: mass number, atomic mass, natural abundance, and stability.
Isotope	Mass	Abundance	Stability
Og-294	294.21392	-	Half-life 0.7 ms

Common uses

Scientific research only

Discovery

Year: 2002
Discovered by: Joint Institute for Nuclear Research, Lawrence Livermore National Laboratory
Country: Russia/USA

Frequently asked questions

Is oganesson a metal?: Oganesson's chemical category has not been confirmed by experiment, so it is listed with unclassified properties.
How many protons does oganesson have?: Oganesson has 118 protons. Its atomic number is 118, which is also the number of electrons in a neutral atom of oganesson.
What group and period is oganesson in?: Oganesson is in group 18 and period 7 of the periodic table, in the p-block.
What is the atomic mass of oganesson?: The atomic mass of oganesson is 294 u (unified atomic mass units).

Keep exploring

Oganesson's row is on the printable element property sheet, and its tile is on the periodic table wall chart - the same numbers as above, laid out for A4 or A3 paper.