Oganesson (Og)
Unknown properties · Radioactive · Synthetic
Oganesson completes period 7 and, for now, the periodic table. Named after superheavy-element pioneer Yuri Oganessian — one of only two people honoured with an element in their lifetime — it is formally a noble gas that is probably neither noble nor a gas.
Position on the periodic table
Atomic properties
| Atomic number | 118 |
|---|---|
| Atomic mass | 294 amu |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d10 7p6 |
| Noble gas shorthand | *[Rn] 5f14 6d10 7s2 7p6 |
| Electrons per shell | 2, 8, 18, 32, 32, 18, 8 |
| Valence electrons (outer shell) | 8 |
| Common oxidation states | None common |
| Electronegativity (Pauling) | Not available |
| Covalent radius (approx.) | Not available |
| First ionization energy | Not available |
| Electron affinity | 5.4 kJ/mol |
Physical properties
| State at 25 °C | Solid |
|---|---|
| Density | 4.95 g/cm³ |
| Melting point | Not available |
| Boiling point | 76.85 °C (350 K) |
| Appearance | Not available |
| Radioactive | Yes |
| Origin | Synthetic (lab-made) |
Electron configuration of oganesson
Oganesson's ground-state electron configuration is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d10 7p6, usually shortened to *[Rn] 5f14 6d10 7s2 7p6. Its electrons occupy 7 shells (2, 8, 18, 32, 32, 18, 8), placing it in period 7 of the p-block. The 8 outer-shell electrons drive its bonding behaviour. Explore it interactively in the electron configuration calculator.
Uses of oganesson
- Fundamental research only
Biological role: None.
Occurrence: Entirely synthetic — only a handful of atoms ever made.
History and discovery
Discovered: 2002 — Joint Institute for Nuclear Research. Name origin: Named after physicist Yuri Oganessian; symbol Og.
Created at Dubna in 2002–2006 by fusing calcium-48 with californium; named oganesson in 2016.
Safety notes
Radioactive; exists for less than a millisecond.
Educational context only — always follow your school's laboratory rules and never handle chemicals without proper supervision. See our disclaimer.
Practice questions
Quick practice: Oganesson
1. What is the chemical symbol of Oganesson?
2. What is the atomic number of Oganesson?
3. Which category does Oganesson belong to?
4. What is the state of Oganesson at room temperature?
5. Which period of the periodic table is Oganesson in?
Oganesson FAQs
What is the atomic number of oganesson?
Oganesson's atomic number is 118 — every oganesson atom has 118 protons in its nucleus.
What is the symbol for oganesson?
Og. Named after physicist Yuri Oganessian; symbol Og.
Is oganesson a metal, nonmetal, or metalloid?
Oganesson is classified as a unknown properties.
What state is oganesson at room temperature?
At about 25 °C, oganesson is a solid.
How many valence electrons does oganesson have?
Oganesson has 8 electrons in its outer shell (shell pattern: 2, 8, 18, 32, 32, 18, 8).
What is oganesson used for?
Key uses include: fundamental research only.
Related elements
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