Copyright © Philip M. Parker, INSEAD. Terms of Use.
Definition: Tungsten |
TungstenNoun1. A heavy gray-white metallic element; the pure form is used mainly in electrical applications; it is found in several ores including wolframite and scheelite. Source: WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. |
Date "tungsten" was first used: 1770. (references) |
Etymology: Tungsten \Tung"sten\, noun. [Sw. tungsten (Compare to Danish tungsteen, German tungstein); tung heavy (akin to Danish tung, Icelandic [thorn]ungr) sten stone. See Stone.]. (references) |
| Domain | Definition |
Chemistry | A dense, steel-grey metal, with a high melting point; it is brittle, hard and has a high resistance to corrosion. Source: European Union. (references) |
Chemistry | Chemical element:atomic number 74. Source: European Union. (references) |
Health | A metallic element with the atomic symbol W, atomic number 74, and atomic weight 183.85. It is used in many manufacturing applications, including increasing the hardness, toughness, and tensile strength of steel; manufacture of filaments for incandescent light bulbs; and in contact points for automotive and electrical apparatus. (references) |
Mining | A hard, brittle, white or gray metallic element. Symbol, W. Also known as wolfram. Found combined in certain minerals such as wolframite, (Fe,Mn)WO 4 ; scheelite, CaWO4 ; huebnerite, MnWO4 ; and ferberite, FeWO4 . Tungsten and its alloys are used extensively for filaments for electric lamps, electron and television tubes, X-ray targets, and numerous space missile and high-temperature applications. See also:wolframite. (references) |
Source: compiled by the editor from various references; see credits. | |
(From Wikipedia, the free Encyclopedia)
Tungsten (formerly wolfram) is a chemical element in the periodic table that has the symbol W and atomic number 74. A very hard, heavy, steel-gray to white transition metal, tungsten is found in several ores including wolframite and scheelite and is remarkable for its robust physical properties. The pure form is used mainly in electrical applications but its many compounds and alloys are widely used in many applications (most notably in light bulb filaments and in space-age superalloys).
General Name, Symbol, Number Tungsten, W, 74 Chemical series Transition metals Group, Period, Block 6 (VIB), 6 , d Density, Hardness 19250 kg/m3, 7.5 Appearance grayish white, lustrous Atomic properties Atomic weight 183.84 amu Atomic radius(calc.) 135 (193) pm Covalent radius 146 pm van der Waals radius no data Electron configuration [Xe]44f14 5d4 6s2 e- 's per energy level 2, 8, 18, 32, 12, 2 Oxidation states (Oxide) 6, 5, 4, 3, 2 (mildly acidic) Crystal structure Cubic body centered Physical properties State of matter solid Melting point 3695 K (6192 °F) Boiling point 5828 K (10031 °F) Molar volume 9.47 ×1010-3 m3/mol Heat of vaporization 824 kJ/mol Heat of fusion 35.4 kJ/mol Vapor pressure 4.27 Pa at 3680 K Speed of sound 5174 m/s at 293.15 K Miscellaneous Electronegativity 2.36 (Pauling scale) Specific heat capacity 130 J/(kg*K) Electrical conductivity 18.9 106/m ohm Thermal conductivity 174 W/(m*K) 1st ionization potential 770 kJ/mol 2nd ionization potential 1700 kJ/mol Most stable isotopes
iso NA half-life DM DE MeV DP 180W 0.12% 7.4 E16 y &alpha no data no data 182W 26.50% 8.3 E18 y α no data no data 183W 14.3% 1.1 E17 y iso no data no data 184W 30.64% 4 E18 y α no data 180Hf 186W 28.43% 6.5 E18 y α no data no data SI units & STP are used except where noted.
Notable characteristics
Pure tungsten is a steel-gray to tin-white hard metal. Tungsten can be cut with a hacksaw when it is very pure (it is brittle and hard to work when impure) and is otherwise worked by forging, drawning, or extruding. This element has the highest melting point (3422 °C), lowest vapor pressure and the highest tensile strength at temperatures above 1650 °C of all metals. Its corrosion resistance is excellent and it can only be attacked slightly by most mineral acids. Tungsten metal forms a protective oxide when exposed to air. When alloyed in small quantities with steel, it greatly increases its hardness.
Applications
Tungsten is a metal with a wide range of uses, the largest of which is as tungsten carbide (W2C, WC) in cemented carbides. Cemented carbides (also called hardmetals) are wear-resistant materials used by the metalworking, mining, petroleum and construction industries. Tungsten is widely used in light bulb and television tube filaments, as well as electrodes, because it can be drawn into very thin metal wires that have have a high melting point. Other uses;
Miscellaneous: Oxides are used in ceramic glazes and calcium/magnesium tungstates are used widely in fluorescent lighting. The metal is also used in X-ray targets, heating elements for electrical furnaces. Salts that contain tungsten are used in the chemical and tanning industries. Tungsten 'bronzes' (so called due to the colour of the tungsten oxides) along with other compounds are used in paints.
- A high melting point also makes tungsten suitable for space-oriented and high temperature uses which include electrical, heating, and welding applications.
- Hardness and density properties make this metal ideal for making heavy metal alloys that are used in armaments, heat sinks, and high-density applications, such as weights and counterweights.
- High speed tool steels (Hastelloy ®, Stellite ®) are often alloyed with tungsten, with tungsten steels containing as much as 18% tungsten.
- Superalloys containing this metal are used in turbine blades, tool steels, and wear-resistant alloy parts and coatings.
- Composites are used as a substitute for lead in bullets and shot.
- Tungsten chemical compounds are used in catalysts, inorganic pigments, and tungsten disulfide high-temperature lubricants which is stable to 500 °C.
- Since this element's thermal expansion is similar to borosilicate glass, it is used for making glass-to-metal seals.
History
Tungsten (Swedish tung sten meaning "heavy stone") was first hypothesized to exist by Peter Woulfe in 1779 who examined wolframite (which was later named for Woulfe) and concluded that it must contain a new substance. In 1781 Carl Wilhelm Scheele ascertained that a new acid could be made from tungstenite. Scheele and Berman suggested that it could be possible to obtain a new metal by reducing tungstic acid. In 1783 José and Fausto Elhuyar found an acid in wolframite that was identical to tungstic acid. In Spain later that year the brothers succeeded in isolating tungsten through reduction of this acid with charcoal. They are credited with the discovery of the element.
Biological role
Enzymes called oxidoreductases use tungsten in a way that is similar to molybdenum by using it in a tungsten-pterin complex.On August 20, 2002 officials representing the US based Centers for Disease Control and Prevention announced that urine tests on leukemia patient families and control group families in the Fallon, Nevada area had shown elevated levels of the metal tungsten in the bodies of both groups. 16 recent cases of cancer in children were discovered in the Fallon area which has now been identified as a "Cancer Cluster." Dr. Carol H. Rubin, a branch chief at the CDC, said data demonstrating a link between tungsten and leukemia are not available at present.
Occurrence
Tungsten is found in the minerals wolframite (iron-manganese tungstate, FeWO4/MnWO4) , scheelite (calcium tungstate, CaWO4), ferberite and huebnerite. Important deposits of these minerals are in Bolivia, California, China, Colorado, Portugal, Russia, and South Korea (with China producing about 75% of the world's supply). The metal is commercially produced by reducing tungsten oxide with hydrogen or carbon.
Compounds
The most common oxidation state of tungsten is +6. Other oxidation states of tungsten are +2, +3, +4, +5, but it exhibits all oxidation states from -2 to 6. Tungsten typically combines with oxygen to form the yellow tungstic oxide, WO3, which dissolves in aqueous alkaline solutions to form tungstate ions, WO42-.
Aqueous polyoxoanions
Aqueous tungstate solutions are noted for the formation of polyoxoanions under neutral and acidic conditions. As tungstate is progressively treated with acid, it first yields the soluble, metastable "paratungstate A" anion, W7O246-, which over hours or days converts to the less soluble "paratungstate B" anion, H2W12O4210-. Further acidification produces the very soluble metatungstate anion, H2W12O406-, after equilibrium is reached. The metatungstate ion exists as a symmetric cluster of twelve tungsten-oxygen octahedra known as the "Keggin" anion. Many other polyoxoanions exist as metastable species. The inclusion of a different atom such as phosphorus in place of the two central hydrogens in metatungstate produces a wide variety of the so-called heteropolyanions.
Isotopes
Naturally occurring tungsten is made of five radioisotopes that have such absurdly long half lifes that for most practical purposes are considered stable. 27 other radioisotopes have been characterized, with the most stable being W-181 with a half-life of 121.2 days, W-185 with a half-life of 75.1 days, W-188 with a half-life of 69.4 days and W-178 with a half-life of 21.6 days. All of the remaining radioactive isotopes have half-lifes that are less than 24 hours, and the majority of these have half-lifes that are less than 8 minutes. This element also has 4 meta states, with the most stable being W-179m (t½ 6.4 minutes).The isotopes of tungsten range in atomic weight from 157.974 amu (W-158) to 189.963 amu (W-190). The primary decay mode before the most abundant isotope, W-184, is electron capture, and the primary mode after is beta decay. The primary decay products before W-184 are element 73 (tantalum) isotopes, and the primary products after are element 75 (rhenium) isotopes.
External links
- WebElements.com - Tungsten
- EnvironmentalChemistry.com - Tungsten
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Tungsten."
Synonyms: TungstenSynonyms: atomic number 74 (n), wolfram (n). (additional references) |
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Source: compiled by the editor from various references; see credits. | |||
| Thumbnail | Description & Credit | Thumbnail | Description & Credit |
 | Production. Tungsten. A piece of tungsten ore mined near Kingman, Arizona and to be processed at a nearby recovery plant. The Boriana mine and plant at this point are producing large amounts of tungsten, for which there are many vital uses in the war effo. Credit: Library of Congress. |  | Kingman (vicinity), Arizona. A laboratory worker at a recovery plant near the Boriana mine selecting a sample of tungsten ore. Credit: Library of Congress. |
Source: pictures compiled by the editor from various references; see picture credits. | |||
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| "Turn it Over" by Kelly Abbott Commentary: "Glass mugs drying on a towel. Tungsten tinge." |
Source: photographs selected by the editor, with permission from the photographers. |
| Subject | Topic | Quote |
Economic History | Cote D'ivoire | Other deposits of tungsten, cobalt, tin, rutile, ilmenite, precious stones, and ornamental stone exist. (references) |
Chad | There is excellent potential for discovery of other metals such as tungsten, tin, iron ore, and bauxite. (references) | |
Bolivia | Major products--natural gas, tin, zinc, coffee, silver, tungsten, wood, gold, jewelry, soybeans, and byproducts. (references) | |
Trade | Burma | On November 26, 1999, the Ministry of Commerce issued Order No. 10/99 that lists the following as restricted export items: rice and rice products, white sugar, red sugar and brown sugar, groundnut and groundnut oil, sesame and sesame oil, mustard and mustard oil, sunflower and sunflower oil, groundnut cake, sesame cake, mustard cake, sunflower cake, cotton and cotton products, petroleum, gems and jewelry, gold, jade, pearls, diamonds, lead, tin, tungsten (wolfram), tin-scheelite, silver, bronze, zinc, coal, other metals, ivory, buffaloes, cows, elephants, horses and rare animals, leather, shrimp, bran, arms, ammunitions, antiques and rubber. (references) |
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
| "Tungsten" is generally used as a noun (singular) -- approximately 100.00% of the time. "Tungsten" is used about 115 times out of a sample of 100 million words spoken or written in English. Its rank is based on over 700,000 words used in the English language. Some parts-of-speech are not covered due to the samples used by the British National Corpus. (note: percents less than one-hundredth of one percent have been omitted) |
| Parts of Speech | Percent | Usage per 100 Million Words | Rank in English |
| Noun (singular) | 100% | 115 | 30,138 |
Source: compiled by the editor from several corpora; see credits.
| Country | Name | Country | Name |
| Japan | Nippon Tungsten Co., Ltd. | South Korea | Korea Tungsten Co., Ltd. |
| (more examples...) |
Source: compiled by the editor from Icon Group International, Inc.
Expressions using "tungsten": iron manganese tungsten ♦ thoriated tungsten cathode ♦ tungsten carbide ♦ Tungsten Compounds ♦ tungsten hexafluoride ♦ tungsten lamp ♦ tungsten ocher ♦ tungsten steel. Additional references. | |
| Hyphenated Usage | |
Beginning with "tungsten": tungsten-alloy, tungsten-carbide, tungsten-halogen, tungsten-tipped. | |
Ending with "tungsten": ferro-tungsten, thoriated-tungsten, tin-tungsten. | |
Containing "tungsten": chrome-tungsten steel. | |
| Source: compiled by the editor from various references; see credits. | |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Expression | Frequency per Day | Expression | Frequency per Day |
tungsten | 422 | pda tungsten | 18 |
palm tungsten | 340 | palm review tungsten | 17 |
c tungsten | 325 | accessory palm tungsten | 14 |
palm tungsten t | 283 | palm pilot tungsten | 14 |
tungsten t | 252 | case palm t tungsten | 13 |
c palm tungsten | 230 | tungsten grinder | 12 |
tungsten electrode | 162 | c case tungsten | 12 |
tungsten w | 132 | trew tungsten | 12 |
palm tungsten w | 113 | gps tungsten | 12 |
tungsten carbide | 60 | review tungsten | 12 |
case t tungsten | 40 | c palm review tungsten | 12 |
c review tungsten | 31 | tungsten halogen | 11 |
t2 tungsten | 31 | blue daylight tungsten | 11 |
handheld palm t tungsten | 26 | palm software t tungsten | 10 |
palm review t tungsten | 26 | tungsten t handheld | 10 |
case palm tungsten | 22 | tungsten case | 10 |
ring tungsten | 20 | case pda tungsten | 9 |
palm t2 tungsten | 19 | tungsten c handheld | 8 |
review t tungsten | 19 | palm pda tungsten | 8 |
gps palm tungsten | 18 | tungsten disulfide | 8 |
| Source: compiled by the editor from various references; see credits. | |||
| Language | Translations for "tungsten"; alternative meanings/domain in parentheses. | |
Albanian | tungsten (wolfram). (various references) | |
Arabic | عنصر فلزي يستخدم لتقسية الفولاذ. (various references) | |
Bulgarian | тунгстен (wolfram), волфрам (wolfram, wolframite). (various references) | |
Chinese | 鎢 , 钨 (Wolfram). (various references) | |
Czech | wolfram. (various references) | |
Danish | tungsten (wolfram), wolfram (wolfram). (various references) | |
Dutch | wolfraam (wolfram). (various references) | |
Esperanto | volframo. (various references) | |
Finnish | volframi. (various references) | |
French | tungstène, wolfram. (various references) | |
German | Wolfram (wolfram). (various references) | |
Greek | βολφράμιο (wolfram). (various references) | |
Hungarian | wolfram, volfrám. (various references) | |
Italian | tungsteno (wolfram). (various references) | |
Japanese Kanji | タンク車 (tank car, tank truck). (various references) | |
Japanese Katakana | タングステン . (various references) | |
Korean | 텅스텐. (various references) | |
Manx | tungsten. (various references) | |
Pig Latin | ungstentay.(various references) | |
Portuguese | volfrâmio (wolfram). (various references) | |
Romanian | tungsten. (various references) | |
Russian | вольфрам (wolfram). (various references) | |
Serbo-Croatian | volfram (wolfram). (various references) | |
Spanish | tungsteno (wolfram). (various references) | |
Swedish | volfram (wolfram). (various references) | |
Turkish | tungsten (wolfram), volfram (wolfram). (various references) | |
Ukrainian | вольфрам (wolfram). (various references) | |
| Source: compiled by the editor from various translation references. | ||
| Language | Period | Translations |
| German | 100 BCE-Modern | Wolfram. (various references) |
| Middle High German | 1100-1500 | ram. (various references) |
| Swedish | 1500-Modern | tungsten. (various references) |
| Source: compiled by the editor from various references. | ||
Derivations | |
Words beginning with "tungsten": tungstens. (additional references) | |
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"Tungsten" is suggested in spellcheckers for the following: thungsten, tungstens, tungstun, tunsten. (additional references) | |
| Source: compiled by the editor, based on several corpora (additional references). | |
| # of Phoneme Matches | Pronunciation | Word(s) rhyming with "tungsten" (pronounced tu"ngstun) |
| 4 | -s t u n | Boston, capstan, clandestine, intestine, piston, predestine, Sexton, teston. |
| 3 | -t u n | fatten, actin, badminton, batten, beaten, begotten, biotin, bitten, boughten, Bouton, brighten, bulletin, Burton, button, Canton, captain, carton, certain, charlatan, chieftain, cosmopolitan, cotton, craton, curtain, Dalton, dentin, dishearten, eaten, enlighten, exoskeleton, flatten, forgotten, fountain, frighten, frostbitten, gelatin, gluten, gotten, guncotton, handwritten, hearten, heighten, highfalutin, intermountain, jetton, kindergarten, kitten, lighten, litten, lovastatin, Manhattan, marten, Martin, Melton, metropolitan, misbegotten, mitten, molten, mountain, mutton, nekton, Newton, overwritten, Parton, Patten, phytoplankton, plankton, plantain, platen, pleasing, ponton, prolactin, puritan, rewritten, rotten, Samaritan, satin, Seton, shorten, Singleton, skeleton, smitten, spartan, straighten, sultan, sweeten, tartan, threaten, tighten, Titan, Triton, typewritten, unbeaten, unbutton, uncertain, underwritten, unwritten, verboten, wanton, wheaten, whiten, written. |
Source: compiled by the editor (additional references); see credits. | ||
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "e-g-n-n-s-t-t-u" | |
-2 letters: unsent. | |
-3 letters: gents, genus, guest, negus, netts, stung, stunt, tents, tunes, tungs, unset. | |
-4 letters: engs, gens, gent, genu, gest, gets, gnus, guns, gust, guts, nest, nets, nett, nuns, nuts, sent, sett, snug, stet, stun, suet, sung, sunn, tegs, tens, tent, test, tets, tugs, tune, tung, tuns, tuts. | |
-5 letters: eng, ens, gen, get, gnu, gun. | |
| Words containing the letters "e-g-n-n-s-t-t-u" | |
+1 letter: tungstens, unsetting. | |
+2 letters: entrusting, stoutening, unsettling. | |
+3 letters: integuments. | |
+4 letters: menstruating, stonecutting, trustingness, understating, unhesitating, unsettlingly. | |
+5 letters: augmentations, conglutinates, counteragents, instrumenting, reinstituting, stonecuttings, understrength, uninteresting. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
| 1. Definition 2. Synonyms 3. Crosswords 4. Usage: Commercial | 5. Images: Photo Album 6. Images: Digital Art 7. Quotations: Non-fiction 8. Usage Frequency | 9. Names: Company Usage 10. Expressions 11. Expressions: Internet 12. Translations: Modern | 13. Translations: Ancient 14. Derivations 15. Rhymes 16. Anagrams | 17. Bibliography |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
