Tungsten , kent as wolfram an aa, 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 ,[4] tho the name is volfram in Swadish fur tae distinguish it frae Scheelite , at in Swadish is alternatively named tungsten .
Quick Facts Pronunciation, Appearance ...
Tungsten, 74 W Tungsten Pronunciation (TUNG -stən ) Appearance riach, lustrous Standard atomic weight A r, std (W)7002183840000000000♠ 183.84(1)[1] Tungsten in the periodic cairt
Mo ↑W ↓Sg
tantalum ← tungsten → rhenium
Atomic nummer (Z ) 74 Group group 6 Period period 6 Block d-block Element category Transeetion metal Electron confeeguration [ Xe ] 4f14 5d4 6s2 [2] Electrons per shell 2, 8, 18, 32, 12, 2 Pheesical properties Phase at STP solit Meltin pynt 3695 K (3422 °C, 6192 °F) Bylin pynt 5828 K (5555 °C, 10031 °F) Density (near r.t. ) 19.25 g/cm3 when liquid (at m.p. ) 17.6 g/cm3 Creetical pynt 13892 K, MPa Heat o fusion 35.3 kJ/mol Heat o vapourisation 806.7 kJ/mol Molar heat capacity 24.27 J/(mol·K) Vapour pressur
P (Pa)
1
10
100
1 k
10 k
100 k
at T (K)
3477
3773
4137
4579
5127
5823
Atomic properties Oxidation states −4, −2, −1, 0, +1, +2, +3, +4 , +5, +6 (a mildly acidic oxide) Electronegativity Pauling scale: 2.36 Atomic radius empirical: 139 pm Covalent radius 162±7 pm Colour lines in a spectral range Spectral lines o tungstenIther properties Naitural occurrence primordial Creestal structur body-centred cubic (bcc)Speed o soond thin rod (annealed) 4620 m/s (at r.t. ) Thermal expansion 4.5 µm/(m·K) (at 25 °C) Thermal conductivity 173 W/(m·K) Electrical resistivity 52.8 n Ω·m (at 20 °C) Magnetic orderin paramagnetic [3] Young's modulus 411 GPa Shear modulus 161 GPa Bulk modulus 310 GPa Poisson ratio 0.28 Mohs haurdness 7.5 Vickers haurdness 3430 MPa Brinell haurdness 2570 MPa CAS Nummer 7440-33-7 History Diskivery Torbern Bergman (1781)First isolation Juan José Elhuyar an Fausto Elhuyar (1783)Main isotopes o tungsten
Iso tope
Abun dance
Hauf-life (t 1/2 )
Decay mode
Pro duct
180 W
0.12%
1.8× 1018 y
α
176 Hf
181 W
syn
121.2 d
ε
181 Ta
182 W
26.50%
>1.7×1020 y
(α )
178 Hf
183 W
14.31%
>8×1019 y
(α )
179 Hf
184 W
30.64%
>1.8×1020 y
(α )
180 Hf
185 W
syn
75.1 d
β−
185 Re
186 W
28.43%
>4.1×1018 y
(α )
182 Hf
(β− β− )
186 Os
Decay modes in parentheses are predictit, but hae nae yet been observed | references
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