Volfram
74
W
Skupina
6
Perioda
6
Blok
d
Protoni
Elektroni
Neutroni
74
74
110
Opća svojstva
Atomski broj
74
Relativna atomska masa
183,84
Maseni broj
184
Kategorija
Prijelazni metali
Boja
Siva
Radioaktivan
Ne
Od njemačke riječi Wolfram; od Wolf, vuk i rȃm, nečist
Kristalna struktura
Kubna prostorno centrirana
Povijest
Torbern Bergman obtained from scheelite an oxide of a new element in 1781.
In 1783, José and Fausto Elhuyar found an acid made from wolframite that was identical to tungstic acid.
Later that year, in Spain, the brothers succeeded in isolating tungsten by reduction of this acid with charcoal, and they are credited with the discovery of the element.
In 1783, José and Fausto Elhuyar found an acid made from wolframite that was identical to tungstic acid.
Later that year, in Spain, the brothers succeeded in isolating tungsten by reduction of this acid with charcoal, and they are credited with the discovery of the element.
Elektrona po ljusci
2, 8, 18, 32, 12, 2
Elektronska konfiguracija
[Xe] 4f14 5d4 6s2
The chemical symbol, W, comes from the original name of the element, Wolfram
Fizikalna svojstva
Agregacijsko stanje
Čvrsto
Gustoća
19,25 g/cm3
Talište
3695,15 K | 3422 °C | 6191,6 °F
Vrelište
5828,15 K | 5555 °C | 10031 °F
Toplina taljenja
35 kJ/mol
Toplina isparavanja
800 kJ/mol
Specifični toplinski kapacitet
0,132 J/g·K
Zastupljenost u Zemljinoj kori
0,00011%
Zastupljenost u svemiru
5×10-8%
CAS broj
7440-33-7
PubChem CID broj
23964
Atomska svojstva
Atomski radijus
139 pm
Kovalentni radijus
162 pm
Elektronegativnost
2,36 (Paulingova ljestvica)
Potencijal ionizacije
7,864 eV
Atomski volumen
9,53 cm3/mol
Toplinska vodljivost
1,74 W/cm·K
Stanja oksidacije
-2, -1, 1, 2, 3, 4, 5, 6
Primjene
Tungsten and its alloys are widely used for filaments in electric bulbs and electronic tubes.
Tungsten carbide is of great importance to the metal-working, mining, and petroleum industries.
Tungsten oxides are used in ceramic glazes and calcium/magnesium tungstates are used widely in fluorescent lighting.
Tungsten carbide is of great importance to the metal-working, mining, and petroleum industries.
Tungsten oxides are used in ceramic glazes and calcium/magnesium tungstates are used widely in fluorescent lighting.
Tungsten is considered to be of low toxicity
Izotopi
Stabilni izotopi
180W, 182W, 183W, 184W, 186WNestabilni izotopi
158W, 159W, 160W, 161W, 162W, 163W, 164W, 165W, 166W, 167W, 168W, 169W, 170W, 171W, 172W, 173W, 174W, 175W, 176W, 177W, 178W, 179W, 181W, 185W, 187W, 188W, 189W, 190W, 191W, 192W