Osmium

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Osmium,  76Os
Osmium crystals.jpg
General properties
Name, seembol osmium, Os
Appearance sillery, blue cast
Pronunciation /ˈɒzmiəm/ OZ-mee-əm
Osmium in the periodic cairt
Hydrogen (diatomic nonmetal)
Helium (noble gas)
Lithium (alkali metal)
Beryllium (alkaline yird metal)
Boron (metalloid)
Carbon (polyatomic nonmetal)
Nitrogen (diatomic nonmetal)
Oxygen (diatomic nonmetal)
Fluorine (diatomic nonmetal)
Neon (noble gas)
Sodium (alkali metal)
Magnesium (alkaline yird metal)
Aluminium (post-transeetion metal)
Silicon (metalloid)
Phosphorus (polyatomic nonmetal)
Sulfur (polyatomic nonmetal)
Chlorine (diatomic nonmetal)
Argon (noble gas)
Potassium (alkali metal)
Calcium (alkaline yird metal)
Scandium (transeetion metal)
Titanium (transeetion metal)
Vanadium (transeetion metal)
Chromium (transeetion metal)
Manganese (transeetion metal)
Airn (transeetion metal)
Cobalt (transeetion metal)
Nickel (transeetion metal)
Capper (transeetion metal)
Zinc (transeetion metal)
Gallium (post-transeetion metal)
Germanium (metalloid)
Arsenic (metalloid)
Selenium (polyatomic nonmetal)
Bromine (diatomic nonmetal)
Krypton (noble gas)
Rubidium (alkali metal)
Strontium (alkaline yird metal)
Yttrium (transeetion metal)
Zirconium (transeetion metal)
Niobium (transeetion metal)
Molybdenum (transeetion metal)
Technetium (transeetion metal)
Ruthenium (transeetion metal)
Rhodium (transeetion metal)
Palladium (transeetion metal)
Siller (transeetion metal)
Cadmium (transeetion metal)
Indium (post-transeetion metal)
Tin (post-transeetion metal)
Antimony (metalloid)
Tellurium (metalloid)
Iodine (diatomic nonmetal)
Xenon (noble gas)
Caesium (alkali metal)
Barium (alkaline yird metal)
Lanthanum (lanthanide)
Cerium (lanthanide)
Praseodymium (lanthanide)
Neodymium (lanthanide)
Promethium (lanthanide)
Samarium (lanthanide)
Europium (lanthanide)
Gadolinium (lanthanide)
Terbium (lanthanide)
Dysprosium (lanthanide)
Holmium (lanthanide)
Erbium (lanthanide)
Thulium (lanthanide)
Ytterbium (lanthanide)
Lutetium (lanthanide)
Hafnium (transeetion metal)
Tantalum (transeetion metal)
Tungsten (transeetion metal)
Rhenium (transeetion metal)
Osmium (transeetion metal)
Iridium (transeetion metal)
Platinum (transeetion metal)
Gold (transeetion metal)
Mercur (transeetion metal)
Thallium (post-transeetion metal)
Leid (post-transeetion metal)
Bismuth (post-transeetion metal)
Polonium (post-transeetion metal)
Astatine (metalloid)
Radon (noble gas)
Francium (alkali metal)
Radium (alkaline yird metal)
Actinium (actinide)
Thorium (actinide)
Protactinium (actinide)
Uranium (actinide)
Neptunium (actinide)
Plutonium (actinide)
Americium (actinide)
Curium (actinide)
Berkelium (actinide)
Californium (actinide)
Einsteinium (actinide)
Fermium (actinide)
Mendelevium (actinide)
Nobelium (actinide)
Lawrencium (actinide)
Rutherfordium (transeetion metal)
Dubnium (transeetion metal)
Seaborgium (transeetion metal)
Bohrium (transeetion metal)
Hassium (transeetion metal)
Meitnerium (unkent chemical properties)
Darmstadtium (unkent chemical properties)
Roentgenium (unkent chemical properties)
Copernicium (transeetion metal)
Ununtrium (unkent chemical properties)
Flerovium (post-transeetion metal)
Ununpentium (unkent chemical properties)
Livermorium (unkent chemical properties)
Ununseptium (unkent chemical properties)
Ununoctium (unkent chemical properties)
Ru

Os

Hs
rheniumosmiumiridium
Atomic nummer (Z) 76
Group, block group 8, d-block
Period period 6
Element category   transeetion metal
Staundart atomic wicht (Ar) 190.23
Electron configuration [Xe] 4f14 5d6 6s2
per shell
2, 8, 18, 32, 14, 2
Pheesical properties
Phase solid
Meltin pynt 3306 K ​(3033 °C, ​5491 °F)
Bylin pynt 5285 K ​(5012 °C, ​9054 °F)
Density near r.t. 22.59 g/cm3
when liquid, at m.p. 20 g/cm3
Heat o fusion 57.85 kJ/mol
Heat o vapourisation 738 kJ/mol
Molar heat capacity 24.7 J/(mol·K)
vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 3160 3423 3751 4148 4638 5256
Atomic properties
Oxidation states 8, 7, 6, 5, 4, 3, 2, 1, 0, -1, -2
(mildly acidic oxide)
Electronegativity Pauling scale: 2.2
Atomic radius empirical: 135 pm
Covalent radius 144±4 pm
Miscellanea
Creestal structur hexagonal close-packed (hcp)
Hexagonal close packed crystal structur for osmium
Speed o soond thin rod 4940 m/s (at 20 °C)
Thermal expansion 5.1 µm/(m·K) (at 25 °C)
Thermal conductivity 87.6 W/(m·K)
Electrical resistivity 81.2 n Ω·m (at 0 °C)
Magnetic orderin paramagnetic[1]
Shear modulus 222 GPa
Bouk modulus 462 GPa
Poisson ratio 0.25
Mohs haurdness 7.0
Brinell haurdness 3920 MPa
CAS Nummer 7440-04-2
History
Diskivery Smithson Tennant (1803)
First isolation Smithson Tennant (1803)
Maist stable isotopes o osmium
iso NA hauf-life DM DE (MeV) DP
184Os 0.02% >5.6×1013 y (β+β+) 1.451 184W
(α) 2.963 180W
185Os syn 93.6 d ε 1.013 185Re
186Os 1.59% 2.0×1015 y α 2.822 182W
187Os 1.96% - (α) 2.7202 183W
188Os 13.24% - (α) 2.1426 184W
189Os 16.15% - (α) 1.9757 185W
190Os 26.26% - (α) 1.3784 186W
191Os syn 15.4 d β 0.314 191Ir
192Os 40.78% >9.8×1012 y (ββ) 0.4135 192Pt
(α) 0.3622 188W
193Os syn 30.11 d β 1.141 193Ir
194Os syn 6 y β 0.097 194Ir
Decay modes in parentheses are predictit, but hae nae yet been observed
· references

Osmium (frae Greek osme (ὀσμή) meanin "smell") is a chemical element wi the seembol Os an atomic nummer 76. It is a haird, brickle, blaeish-white transeetion metal in the platinum faimily an is the densest naiturally occurrin element, wi a density o 22.59 g/cm3. It is foond as a trace element in alloys, maistly in platinum ores. Its alloys wi platinum, iridium, an ither platinum group metals are employed in fountain pen tips, electrical contacts, an ither applications whaur extreme durability an hairdness are needit.[2]

References[eedit | eedit soorce]

  1. Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics 81st edition, CRC press.
  2. Hammond "Osmium", C. R., p. 4–25 in Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.