Osmium
Osmium (锇, symbol Os) is chemical element number 76, a Transition Metal in period 6, group 8 of the periodic table, with a standard atomic weight of about 190.23. Densest naturally occurring element. Bluish-white, used in fountain pen tips and electrical contacts.
Properties
| Atomic number | 76 |
|---|---|
| Symbol | Os |
| Atomic mass | 190.23 u |
| Category | Transition Metal |
| Period | 6 |
| Group | 8 |
| Electron configuration | [Xe] 4f¹⁴ 5d⁶ 6s² |
| Electronegativity | 2.2 |
| Covalent radius | 144 pm |
| Density | 22.59 g/cm³ |
| Melting point | 3306 K |
| Boiling point | 5285 K |
| Discovery | Smithson Tennant, 1803 |
Overview
Densest naturally occurring element. Bluish-white, used in fountain pen tips and electrical contacts. Osmium (symbol Os) is chemical element number 76, sitting in period 6, group 8 of the periodic table and classed as a Transition Metal. As a transition metal it commonly shows several oxidation states, forms coloured compounds, and is widely used in catalysts and alloys.
With 2 electrons in its outermost shell, Osmium bonds accordingly; full configuration [Xe] 4f¹⁴ 5d⁶ 6s², electronegativity 2.2. At room temperature it is normally a solid (a very high melting point); it melts near 3306 K (3032.9 °C), boils near 5285 K (5011.9 °C), has a density around 22.59 g/cm³.
Common applications range across Structural / Alloys and Precious Metal. It is regarded as a moderate-hazard element, so handle it with appropriate care. It was first described by Smithson Tennant in 1803.
Electron shells
Electrons per shell: 2 · 8 · 18 · 32 · 14 · 2
Main uses
- Structural / Alloys
- Precious Metal
Hazard
Compounds containing Osmium
No compounds in this knowledge base contain Osmium yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.