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 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance


Name: Osmium Symbol: Os
Group: Trans. Met. Atomic weight: 190.2
Density @ 293 K: 22.40 g/cm3 Atomic volume: 8.49 cm3/mol
Group: Trans. Met. discovered: 1804


state (s, l, g): s
melting point: 3318.2 K boiling point: 5298 K
Heat of fusion: 31.80 kJ/mol Heat of vaporization: 746.0 kJ/mol


1st ionization energy: 840 kJ/mole
electronegativity: 2.2 2nd ionization energy: kJ/mole
electron affinity: 110 kJ/mole 3rd ionization energy: kJ/mole
Specific heat: 0.13 J/gK heat atomization: 791 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,32,14,2 electron configuration: [Xe] 4f14 5d6 6s2
minimum oxidation number: -2 maximum oxidation number: 8
min. common oxidation no.: 0 max. common oxidation no.: 4

Appearance & Characteristics:

structure: hcp: hexagonal close pkd color: bluish-white
uses: hard alloys,phono needles toxicity:
hardness: 7 mohs characteristics: hard, dense, inert <100 C


reaction with air: none
reaction with 6M HCl: none reaction with 6M HCl: none
reaction with 15M HNO3: mild, =>OsO4 reaction with 6M NaOH:

Other Forms:

number of isotopes: 7 hydride(s): none
oxide(s): OsO2 OsO4 chloride(s): OsCl3 OsCl4 OsCl5


ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: 135 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): pm


thermal conductivity: 87.6 J/m-sec-deg
electrical conductivity: 105.263 1/mohm-cm polarizability: 8.5 A^3


source: nickel ores (sulfides)
rel. abund. solar system: -0.171 log abundance earth's crust: -2.8 log
cost, pure: 7700 $/100g cost, bulk: $/100g