Wolfram
74
W
Grupă
6
Perioadă
6
Bloc
d
Protoni
Electroni
Neutroni
74
74
110
Proprietăți Generale
Număr atomic
74
Masă atomică
183,84
Numar de masa
184
Categorie
Metale de tranziție
Culoare
Gri
Radioactive
Nu
Din suedeză, tung sten, însemnând piatră grea
Structură cristalină
Corp Centrat Cubic
Istoric
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.
Electroni pe nivelul de energie
2, 8, 18, 32, 12, 2
Configurație electronică
[Xe] 4f14 5d4 6s2
The chemical symbol, W, comes from the original name of the element, Wolfram
Proprietăți Fizice
Fază
Solid
Densitate
19,25 g/cm3
Punct de topire
3695,15 K | 3422 °C | 6191,6 °F
Punct de fierbere
5828,15 K | 5555 °C | 10031 °F
Energie de fuziune
35 kJ/mol
Energie de evaporare
800 kJ/mol
Căldură specifică
0,132 J/g·K
Abundența în scoarța Pământului
0,00011%
Abundența în Univers
5×10-8%
Numarul CAS
7440-33-7
Număr CID PubChem
23964
Proprietăți Atomice
Rază atomică
139 pm
Rază de covalență
162 pm
Electronegativitate
2,36 (Scara lui Pauling)
Potențial de ionizare
7,864 eV
Volum molar
9,53 cm3/mol
Conductivitate termică
1,74 W/cm·K
Număr de oxidare
-2, -1, 1, 2, 3, 4, 5, 6
Aplicații
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
Izotopi stabili
180W, 182W, 183W, 184W, 186WIzotopi instabili
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