Quick answerOsmium (Os) is a transition metal with atomic number 76 and an atomic mass of 190.23 (2023), in group 8, period 6. It was discovered by Smithson Tennant in 1803. It is used for fountain pen tips and electrical contacts. Its electron configuration is [Xe] 4f14 5d6 6s2.
Osmium is the densest naturally occurring element, and its hard alloys tip fountain pens and electrical contacts.
Key facts
| Symbol | Os |
|---|---|
| Atomic number | 76 |
| Atomic mass | 190.23 (IUPAC standard atomic weight, 2023) |
| Category | transition metal |
| Group | 8 |
| Period | 6 |
| Block | d-block |
| Electron configuration | [Xe] 4f14 5d6 6s2 |
| Discovered | Smithson Tennant, 1803 |
| Uses | fountain pen tips, electrical contacts, instrument pivots, catalysts, alloys |
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Keep exploring
- Periodic table — all 118 elements
- Cadmium (Cd) — another transition metal, atomic number 48
- Hafnium (Hf) — another transition metal, atomic number 72
- Tantalum (Ta) — another transition metal, atomic number 73
- Tungsten (W) — another transition metal, atomic number 74
- Rhenium (Re) — another transition metal, atomic number 75
- Iridium (Ir) — another transition metal, atomic number 77
- Platinum (Pt) — another transition metal, atomic number 78
- Gold (Au) — another transition metal, atomic number 79
- Mercury (Hg) — another transition metal, atomic number 80
- Rutherfordium (Rf) — another transition metal, atomic number 104
- All transition metal elements — on the periodic table
Sources & last updated
- CIAAW — Standard Atomic Weights
- PubChem Periodic Table
- Wikipedia — Timeline of chemical element discoveries
Last updated: . Figures are shown with their year; where sources disagree, the value is left out rather than estimated.