Tungsten
Tungsten General
| Name:Tungsten | Symbol:W |
| Type:Transition Metal | Atomic weight:183.85 |
| Density @ 293 K:19.3 g/cm3 | Atomic volume:9.53 cm3/mol |
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Discovered:
In 1779 Peter Woulfe deduced the existence of a new element - Tungsten - from his analysis of the mineral wolframite (an iron manganese tungstate mineral). Tungsten was isolated by Fausto and Juan Jose de Elhuyar in 1783 by reduction acidified wolframite with charcoal. The element name comes from the Swedish words 'tung sten', meaning heavy stone. The chemical symbol, W, comes from the original name of the element, Wolfram. |
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Tungsten States
| State (s, l, g):solid | |
| Melting point:3695 K (3422 °C) | Boiling point:5823 K (5550 °C) |
Tungsten Energies
| Specific heat capacity: 0.13 J g-1 K-1 | Heat of atomization:860 kJ mol-1 |
| Heat of fusion:35.40 kJ mol-1 | Heat of vaporization :824.0 kJ mol-1 |
| 1st ionization energy:770 kJ mol-1 | 2nd ionization energy:1700 kJ mol-1 |
| 3rd ionization energy: kJ mol-1 | Electron affinity: 78.6 kJ mol-1 |
Tungsten Oxidation & Electrons
| Shells:2,8,18,32,12,2 | Electron configuration:[Xe] 4f14 5d4 6s2 |
| Minimum oxidation number:-2 | Maximum oxidation number:6 |
| Min. common oxidation no.:0 | Max. common oxidation no.:6 |
| Electronegativity (Pauling Scale):2.36 | Polarizability volume:11.1 Å3 |
Tungsten Appearance & Characteristics
| Structure:bcc: body-centered cubic | Color:silvery-white |
| Hardness:7.5 mohs | |
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Harmful effects:
Tungsten is considered to be of low toxicity. |
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Characteristics:
Tungsten is a very hard, dense, silvery-white, lustrous metal that tarnishes in air, forming a protective oxide coating. In powder form tungsten is gray in color. Uses: Tungsten and its alloys are widely used for filaments in older style (not energy saving) electric bulbs and electronic tubes. It is used for making heavy metal alloys because of its hardness. Tungsten is used for high-temperature applications such as welding. |
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Tungsten Reactions
| Reaction with air:w/ht, ⇒ WO3 | Reaction with 6 M HCl:none |
| Reaction with 15 M HNO3:none | Reaction with 6 M NaOH: |
Tungsten Compounds
| Oxide(s):WO2, WO3 (tungstic oxide) | Chloride(s):WCl2, WCl4, WCl6 |
| Hydride(s): |
Tungsten Radius
| Atomic radius:139 pm | Ionic radius (1+ ion):pm |
| Ionic radius (2+ ion):pm | Ionic radius (3+ ion):pm |
| Ionic radius (2- ion):pm | Ionic radius (1- ion):pm |
Tungsten Conductivity
| Thermal conductivity:173 W m-1 K-1 | Electrical conductivity:18.2 x 106 S m-1 |
Tungsten Abundance & Isotopes
| Abundance earth's crust:1.25 parts per million by weight, 0.1 parts per million by moles | |
| Abundance solar system: 4 parts per billion by weight, 30 part per trillion by moles | |
| Cost, pure:$11 per 100g | |
| Cost, bulk: $2.95 per 100g | |
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Source:
Tungsten is not found free in nature. The principal ores of tungsten are wolframite (an iron manganese tungstate) and scheelite (calcium tungstate, CaWO3). Comercially, the metal is obtained by reducing tungsten oxide with hydrogen or carbon. |
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Isotopes:
Tungsten has 33 isotopes whose half-lives are known with mass numbers from 158 to 190. Of these, three are stable: 180W, 182W, and 186W. |
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Tungsten Other
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Other:
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