Wolfram
74
W
Skupina
6
Perioda
6
Blok
d
Protony
Elektrony
Neutrony
74
74
110
Hlavní vlastnosti
Atomové číslo
74
Atomová hmotnost
183,84
Hmotnostní číslo
184
Kategorie
Přechodné kovy
Barva
Šedá
Radioaktivní
Ne
From Swedish, tung sten meaning heavy stone
Krystalografická soustava
Kubická prostorově centrovaná
Historie
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.
Elektronů v obalu
2, 8, 18, 32, 12, 2
Elektronová konfigurace
[Xe] 4f14 5d4 6s2
The chemical symbol, W, comes from the original name of the element, Wolfram
Fyzické vlastnosti
Skupenství
Pevná
Hustota
19,25 g/cm3
Teplota tání
3695,15 K | 3422 °C | 6191,6 °F
Teplota varu
5828,15 K | 5555 °C | 10031 °F
Skupenské teplo tání
35 kJ/mol
Skupenské teplo varu
800 kJ/mol
Měrná tepelná kapacita
0,132 J/g·K
Hojnost v zemské kůře
0,00011%
Hojnost ve vesmíru
5×10-8%
Číslo CAS
7440-33-7
PubChem CID číslo
23964
Atomové vlastnosti
Atomový poloměr
139 pm
Kovalentní poloměr
162 pm
Elektronegativita
2,36 (Paulingova stupnice)
Ionizační potenciál
7,864 eV
Molární objem
9,53 cm3/mol
Tepelná vodivost
1,74 W/cm·K
Oxidační čísla
-2, -1, 1, 2, 3, 4, 5, 6
Aplikace
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
Izotopy
Stabilní izotopy
180W, 182W, 183W, 184W, 186WNestabilní izotopy
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