76
190.23
Os
Osmium
Identification
CAS Number: 7440-04-2
Discovery Year: 1804
Discoverer: Smithson Tenant
Discovery Location: England
Properties
Atomic Dimensions
Atomic Radius: 130 pm →
Atomic Radius (Rahm): 244 pm
Covalent Radius: 144 pm →Van der Waals Radius: 216 pm
Metallic Radius: 126 pm
Atomic Volume: 8.43 cm³/mol
Lattice Constant: 2.74 Å
Thermodynamics
Electronic Structure
Electron Config: [Xe] 4f14 5d6 6s2
Block: d
Period: 6 →Group: 8 →Electronegativity: 2.2 →Electron Affinity: 1.1 eV →Oxidation States: -2, 0, +2, +3, +4, +6, +8
Abundance & Geochemistry
Crust Abundance: 0.0015 mg/kg
Geochemical Class: noble metal
Goldschmidt Class: siderophile
About
Hard blue-white metallic transition element. Found with platinum and used in some alloys with platinum and iridium.
Isotopes
Os-192 192 40.78%
Os-190 190 26.26%
Os-189 189 16.15%
Os-188 188 13.24%
Os-187 187 1.96%
Os-186 186 1.59%
Os-184 184 0.0200%