From Wikipedia, the free encyclopediaOsmium (from Greek osme (ὀσμή) meaning "smell") is a chemical element with symbol Os and atomic number 76. It is a hard, brittle, bluish-white transition metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element, with a density of 22.59 g/cm3. | |||||
Osmium in the periodic table | |||||
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Symbol | Os | ||||
Atomic number | 76 | ||||
Group | 8 | ||||
Period | 6 | ||||
Block | d | ||||
Element category | Transition Metal | ||||
Physical properties | |||||
Phase at STP | Solid | ||||
Density | 22.59 g/cm3 | ||||
Atomic weight | 190.233 u | ||||
Melting point | 3306 K 3032.85 °C 5491.13 °F | ||||
Boiling point | 5285 K 5011.85 °C 9053.33 °F | ||||
Atomic properties | |||||
Electronegativity (Pauling Scale) | 2.2 | ||||
Electron affinity | 103.99 kJ/mol | ||||
Oxidation states | −4, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7, +8 (a mildly acidic oxide) | ||||
Ionization energies |
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Electron configuration | |||||
Elektronkonfiguration (shorthand) | [Xe] 4f14 5d6 6s2 | ||||
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d6 6s2 | ||||
Electrons per shell | 2, 8, 18, 32, 14, 2 | ||||
History | |||||
Discovered | 1803 | ||||
Discovered by | Smithson Tennant |