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Native tungsten

Tungsten,  74W
Wolfram evaporated crystals and 1cm3 cube.jpg
General properties
Pronunciation /ˈtʌŋstən/ (TUNG-stən)
Alternative name wolfram, pronounced: /ˈwʊlfrəm/ (WUUL-frəm)
Appearance grayish white, lustrous
Standard atomic weight (Ar, standard) 183.84(1)
Tungsten in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Mo

W

Sg
tantalumtungstenrhenium
Atomic number (Z) 74
Group group 6
Period period 6
Element category   transition metal
Block d-block
Electron configuration [Xe] 4f14 5d4 6s2
Electrons per shell
2, 8, 18, 32, 12, 2
Physical properties
Phase (at STP) solid
Melting point 3695 K ​(3422 °C, ​6192 °F)
Boiling point 6203 K ​(5930 °C, ​10706 °F)
Density (near r.t.) 19.25 g/cm3
when liquid (at m.p.) 17.6 g/cm3
Heat of fusion 52.31 kJ/mol
Heat of vaporization 774 kJ/mol
Molar heat capacity 24.27 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 3477 3773 4137 4579 5127 5823
Atomic properties
Oxidation states 6, 5, 4, 3, 2, 1, 0, −1, −2, −4 ​(a mildly acidic oxide)
Electronegativity Pauling scale: 2.36
Ionization energies
  • 1st: 770 kJ/mol
  • 2nd: 1700 kJ/mol
Atomic radius empirical: 139 pm
Covalent radius 162±7 pm
Color lines in a spectral range
Miscellanea
Crystal structure body-centered cubic (bcc)
Body-centered cubic crystal structure for tungsten
Speed of sound thin rod 4620 m/s (at r.t.) (annealed)
Thermal expansion 4.5 µm/(m·K) (at 25 °C)
Thermal conductivity 173 W/(m·K)
Electrical resistivity 52.8 nΩ·m (at 20 °C)
Magnetic ordering paramagnetic
Magnetic susceptibility +59.0·10−6 cm3/mol (298 K)
Young's modulus 411 GPa
Shear modulus 161 GPa
Bulk modulus 310 GPa
Poisson ratio 0.28
Mohs hardness 7.5
Vickers hardness 3430–4600 MPa
Brinell hardness 2000–4000 MPa
CAS Number 7440-33-7
History
Discovery Carl Wilhelm Scheele (1781)
First isolation Juan José Elhuyar and Fausto Elhuyar (1783)
Named by Torbern Bergman (1781)
Main isotopes of tungsten
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
180W 0.12% 1.8×1018 y α 176Hf
181W syn 121.2 d ε 181Ta
182W 26.50% stable
183W 14.31% stable
184W 30.64% stable
185W syn 75.1 d β 185Re
186W 28.43% stable
| references |

Tungsten, or wolfram, is a chemical element with symbol W and atomic number 74. The name tungsten comes from the former Swedish name for the tungstate mineral scheelite, from tung sten "heavy stone". Tungsten is a rare metal found naturally on Earth almost exclusively in chemical compounds. It was identified as a new element in 1781, and first isolated as a metal in 1783. Its important ores include wolframite and scheelite.

The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all the elements discovered, melting at 3422 °C (6192 °F, 3695 K). It also has the highest boiling point, at 5930 °C (10706 °F, 6203 K). Its density is 19.3 times that of water, comparable to that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work. However, pure single-crystalline tungsten is more ductile, and can be cut with a hard-steel hacksaw.

Tungsten's many alloys have numerous applications, including incandescent light bulb filaments, X-ray tubes (as both the filament and target), electrodes in TIG welding, superalloys, and radiation shielding. Tungsten's hardness and high density give it military applications in penetrating projectiles. Tungsten compounds are also often used as industrial catalysts.


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