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76Os190.233
Osmium
Transition MetalOsmium (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.
Phase: SolidAppearance: silvery, blue cast
2, 8, 18, 32, 14, 2
Physical Properties
Atomic Mass190.233 u
Density22.59 g/cm³
Melting Point3306 K
Boiling Point5285 K
Molar Heat24.7 J/(mol·K)
Period6
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d6
Semantic Config[Xe] 4f14 5d6 6s2
Shells2, 8, 18, 32, 14, 2
Electron Affinity103.99 kJ/mol
Electronegativity2.2
Ionization Energies
IE1: 840 kJ/molIE2: 1600 kJ/mol
Discovery
Discovered bySmithson Tennant