The Element Tungsten
[Click for Isotope Data]
Atomic Number: 74
Atomic Weight: 183.84
Melting Point: 3695 K (3422°C or 6192°F)
Boiling Point: 5828 K (5555°C or 10031°F)
Density: 19.3 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 6 Group Number: 6 Group Name: none
What's in a name? From the Swedish words tung sten, which mean "heavy stone." Tungsten's chemical symbol comes from its eariler, Germanic name, Wolfram. The name Wolfram comes from the mineral wolframite, in which it was discovered. Wolframite means "the devourer of tin" since the mineral interferes with the smelting of tin.
Say what? Tungsten is pronounced as TUNG-sten.
History and Uses:
Tungsten was discovered by Juan José and Fausto Elhuyar, Spanish chemists and brothers, in 1783 in samples of the mineral wolframite ((Fe, Mn)WO4). Today, tungsten is primarily obtained from wolframite and scheelite (CaWO4) using the same basic method developed by José and Elhuyar. Tungsten ores are crushed, cleaned and treated with alkalis to form tungsten trioxide (WO3). Tungsten trioxide is then heated with carbon or hydrogen gas (H2), forming tungsten metal and carbon dioxide (CO2) or tungsten metal and water vapor (H2O).
Pure tungsten is a light gray or whitish metal that is soft enough to be cut with a hacksaw and ductile enough to be drawn into wire or extruded into various shapes. If contaminated with other materials, tungsten becomes brittle and difficult to work with. Tungsten has the highest melting point of all metallic elements and is used to make filaments for incandescent light bulbs, fluorescent light bulbs and television tubes. Tungsten expands at nearly the same rate as borosilicate glass and is used to make metal to glass seals. Tungsten is also used as a target for X-ray production, as heating elements in electric furnaces and for parts of spacecraft and missiles which must withstand high temperatures.
Tungsten is alloyed with steel to form tough metals that are stable at high temperatures. Tungsten-steel alloys are used to make such things as high speed cutting tools and rocket engine nozzles.
Tungsten carbide (WC) is an extremely hard tungsten compound. It is used in the tips of drill bits, high speed cutting tools and in mining machinery. Tungsten disulfide (WS2) is a dry lubricant that can be used to temperatures as high as 500°C. Tungsten forms compounds with calcium and magnesium that have phosphorescent properties and are used in fluorescent light bulbs.
Estimated Crustal Abundance: 1.25 milligrams per kilogram
Estimated Oceanic Abundance: 1×10-4 milligrams per liter
Number of Stable Isotopes: 2 (View all isotope data)
Ionization Energy: 7.98 eV
Oxidation States: +6
3s2 3p6 3d10
4s2 4p6 4d10 4f14
5s2 5p6 5d4