118Og[294]
Oganesson (Og)
Element 118 · Noble gas
Oganesson (Og) is a chemical element with atomic number 118. It is classified as a noble gas in period 7, group 18 of the periodic table (the p-block). Its most stable known isotope has mass number 294 and its ground-state electron configuration is [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁶. Its properties are largely predicted, as only a few atoms have ever been produced.
Oganesson facts
| Atomic number (Z) | 118 |
|---|---|
| Symbol | Og |
| Mass number of most stable isotope | [294] |
| Category | Noble gas |
| Group | 18 |
| Period | 7 |
| Block | p-block |
| Electron configuration | [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁶ |
| Electronegativity (Pauling) | — |
| State at 20 °C | Unknown (synthetic) |
| Protons / electrons | 118 / 118 |
| Neutrons (most common isotope, approx.) | 176 |
| Molar mass | 294 g/mol |