Tungsten

Frae Wikipedia
Lowp tae: navigation, rake
Tungsten
74W
Mo

W

Sg
tantalumtungstenrhenium
Appearance
grayish white, lustrous
General properties
Name, seembol, nummer tungsten, W, 74
Pronunciation /ˈtʌŋstən/ TUNG-stən;
/ˈwʊlfrəm/ WUUL-frəm
Element category transeetion metal
Group, period, block 6, 6, d
Staundart atomic wicht 183.84
Electron confeeguration [Xe] 4f14 5d4 6s2[1]
2, 8, 18, 32, 12, 2
Electron shells of tungsten (2, 8, 18, 32, 12, 2)
History
Discovery Torbern Bergman (1781)
First isolation Juan José Elhuyar an Fausto Elhuyar (1783)
Physical properties
Phase solid
Density (near r.t.) 19.25 g·cm−3
Liquid density at m.p. 17.6 g·cm−3
Meltin pynt 3695 K, 3422 °C, 6192 °F
Boilin pynt 5828 K, 5555 °C, 10031 °F
Creetical pynt 13892 K, MPa
Heat o fusion 35.3 kJ·mol−1
Heat o vaporization 806.7 kJ·mol−1
Molar heat capacity 24.27 J·mol−1·K−1
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
(mildly acidic oxide)
Electronegativity 2.36 (Pauling scale)
Ionization energies 1st: 770 kJ·mol−1
2nd: 1700 kJ·mol−1
Atomic radius 139 pm
Covalent radius 162±7 pm
Miscellanea
Crystal structure body-centered cubic
Tungsten has a body-centered cubic crystal structure
Magnetic orderin paramagnetic[2]
Electrical resistivity (20 °C) 52.8 nΩ·m
Thermal conductivity 173 W·m−1·K−1
Thermal expansion (25 °C) 4.5 µm·m−1·K−1
Speed o soond (thin rod) (r.t.) (annealed) 4620 m·s−1
Young's modulus 411 GPa
Shear modulus 161 GPa
Bulk modulus 310 GPa
Poisson ratio 0.28
Mohs hairdness 7.5
Vickers hairdness 3430 MPa
Brinell hairdness 2570 MPa
CAS registry nummer 7440-33-7
Most stable isotopes
Main article: Isotopes o tungsten
iso NA hauf-life DM DE (MeV) DP
180W 0.12% 1.8×1018 y α 2.516 176Hf
181W syn 121.2 d ε 0.188 181Ta
182W 26.50% >1.7×1020 y (α) 1.772 178Hf
183W 14.31% >8×1019 y (α) 1.680 179Hf
184W 30.64% >1.8×1020 y (α) 1.123 180Hf
185W syn 75.1 d β 0.433 185Re
186W 28.43% >4.1×1018 y (α) 1.656 182Hf
(ββ) - 186Os
Decay modes in parentheses are predictit, but hae nae yet been observed
· r

Tungsten, an aa kent as wolfram, is a chemical element wi the chemical seembol W an atomic nummer 74. The wird tungsten comes frae the Swadish leid tung sten directly translatable tae hivy stane,[3] tho the name is volfram in Swadish tae distinguish it frae Scheelite, which in Swadish is alternatively named tungsten.

References[eedit | eedit soorce]

  1. "Why does Tungsten not 'Kick' up an electron from the s sublevel ?". Retrieved 2008-06-15. 
  2. Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics 81st edition, CRC press.
  3. "Tungsten". Oxford English Dictionary (3rd ed.). Oxford University Press. 2001.