Tungsten , including Technical Data, Safety Data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure,ionization energy, abundance on Earth, conductivity and thermal properties are included.  Tungsten has the highest melting point of all the metallic elements and because of this has its first significant commercial application as the filament in incandescent light bulbs and fluorescent light bulbs. Tungsten is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity); metals in the form of foil, sputtering target, and rod, and compounds as submicron and nanopowder. Later it was used in the first television tubes. The first imaging equipment involved X-ray bombardment of a tungsten target. Tungsten expands at nearly the same rate as borosilicate glass and is used to make metal to glass seals. It is the primary metal in heating elements for electric furnaces and in any components where high pressure/temperature environments are expected, such as aerospace and engine systems. Tungsten is alloyed in steel to improve its ability to operate in high temperatures. Tungsten carbide is used in drill bits and cutting tools because it is one of the hardest commercial materials.. Tungsten forms compounds with calcium and magnesium that have phosphorescent properties and are used in the glass coatings for fluorescent light bulbs. Other tungsten chemical compounds are used in catalysts and lubricants. In reference to its density, Tungsten gets its name from the swedish words tung and sten meaning heavy stone.

Tungsten facts, including appearance, CAS #, and molecular formula and safety data, research and properties are available for many specific states, forms and shapes on the product pages listed to the left. Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes.Nanoparticles and nanopowdersprovide ultra high surface area which nanotechnology research and recent experiments demonstrate function to create new and unique properties and benefits. 

Oxides are available in forms including powders and dense pellets for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Tungsten is available in soluble forms including chlorides, nitrates and acetates. These compounds are also manufactured as solutions at specified stoichiometries. 

Tungsten is a Block D, Group 6, Period 6 element. The number of electrons in each of Tungsten‘s shells is 2, 8, 18, 32, 12, 2 and its electronic configuration is [Xe] 4f14 5d4 6s2. In its elemental form tungsten‘s CAS number is 7440-33-7. The tungsten atom has a radius of 137.pm and it‘s Van der Waals radius is 200.pm. Tungsten is considered to be only mildly toxic. 

All elemental metals, compounds and solutions may be synthesized in ultra high purity (e.g. 99.999%) for laboratory standards, advanced electronic, thin fillm deposition using sputtering targets and evaporation materials, metallurgy and optical materials and other high technology applications. Information is provided for stable (non-radioactive) isotopes. Organo-Metallic Tungsten compounds are soluble in organic or non-aqueous solvents. SeeAnalytical Services for information on available certified chemical and physical analysis techniques including MS-ICP, X-Ray Diffraction, PSD and Surface Area (BET) analysis. 

Tungsten was first discovered by Fausto and Juan Jose de Elhuyar in 1783.

Abundance. The following table shows the abundance of tungsten and each of its naturally occurringisotopes on Earth along with the atomic mass for each isotope.

Isotope	Atomic Mass	% Abundance on Earth
W-180	179.946706	0.13
W-182	181.948206	26.3
W-183	182.950224	14.3
W-184	183.950933	30.67
W-186	185.954362	28.6

The following table shows the abundance of Tungsten present in the human body and in the universe scaled to parts per billion (ppb) by weight and by atom:

	Typical Human Body	Universe
by Weight	no data	0.5 ppb
by Atom	no data	0.003 ppb

Safety Data and Biological Role. The safety data for tungsten metal, nanoparticles and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the left margin. Tungsten compounds have a small biological role in some enzymes. 

Ionization Energy. The ionization energy for tungsten (the least required energy to release a single electron from the atom in it‘s ground state in the gas phase) is stated in the following table:

1st Ionization Energy	758.77 kJ mol-1
2nd Ionization Energy	- kJ mol-1
3rd Ionization Energy	- kJ mol-1

Conductivity. As to tungsten‘s electrical and thermal conductivity, the electrical conductivity measured as to electrical resistivity @ 20 ?C is 5.4 μΩcm and its electronegativities (or its ability to draw electrons relative to other elements) is 1.7. The thermal conductivity of tungsten is 174 W m-1 K-1. 

Thermal Properties. The melting point and boiling point for tungsten are stated below. The following chart sets forth the heat of fusion, heat of vaporization and heat of atomization.

Heat of Fusion	35.2 kJ mol-1
Heat of Vaporization	824.2 kJ mol-1
Heat of Atomization	848.1 kJ mol-1