Tantalum


 * Tantalum** is a chemical element with the symbol **Ta** and atomic number 73. Previously known as //tantalium//, the name comes from Tantalus, a character from Greek mythology. Tantalum is a rare, hard, blue-gray, lustrous transition metal that is highly corrosion resistant. It is part of the refractory metals group, which are widely used as minor component in alloys. The chemical inertness of tantalum makes it a valuable substance for laboratory equipment and a substitute for platinum, but its main use today is in tantalum capacitors in electronic equipment such as mobile phones, DVD players, video game systems and computers. Tantalum, always together with the chemically similar niobium, occurs in the minerals tantalite, columbite and coltan.


 * Atomic Number:** 73
 * Atomic Weight:** 180.94788
 * Melting Point:** 3290 K (3017°C or 5463°F)
 * Boiling Point:** 5731 K (5458°C or 9856°F)
 * Density:** 16.4 grams per cubic centimeter
 * Phase at Room Temperature:** Solid
 * Element Classification:** Metal
 * Period Number:** 6 **Group Number:** 5 **Group Name:** none
 * Heat of fusion**: 36.57 kJ/mol^-1
 * Speed of sound (thin rod):** (20 degrees C) 3400 m/s^-1

Tantalum was discovered by Anders Gustaf Ekenberg, a Swedish chemist, in 1802 in minerals obtained from Ytterby, Sweden. Many scientists believed that he had only discovered an allotrope of niobium, an element that is chemically similar to tantalum. The issue was finally settled in 1866 when, Jean Charles Galissard de Marignac, a Swiss chemist, proved that tantalum and niobium were two distinct elements. The first relatively pure samples of tantalum were first produced in 1907. Today, tantalum is primarily obtained from the minerals columbite ((Fe, Mn, Mg)(Nb, Ta)2O6), tantalite ((Fe, Mn)(Ta, Nb)2O6) and euxenite ((Y, Ca, Er, La, Ce, U, Th)(Nb, Ta, Ti)2O6). Tantalum is a strong, ductile metal that is nearly immune to chemical attack at room temperatures. It can be drawn into a fine wire that is used to evaporate metals, such as aluminum. It has a high melting point and is frequently used as a substitute for platinum, which is more expensive. Tantalum is used to make components for chemical plants, nuclear power plants, airplanes and missiles. Tantalum does not react with bodily fluids and is used to make surgical equipment. Tantalum also does not irritate the body and is used to make surgical sutures as well as implants, such as artificial joints and cranial plates. Tantalum is alloyed with steel to increase steel's ductility, strength and melting point. Tantalum pentoxide (Ta2O5), one of tantalum's compounds, is a dielectric material and is used to make capacitors. It is also used to make a glass with a high index of refraction that is used in camera lenses. A composite consisting of tantalum carbide (TaC) and graphite is one of the hardest materials known and is used on the cutting edges of high-speed machine tools.
 * History and Uses:**

Tantalum metal has a number of important uses. It is used to make steels with desirable properties such as high melting point, high strength, good ductility. These find use in aircraft and missile manufacture. It is very inert and so useful in the chemical and nuclear industries to line reactors. Tantalum wires were those used first for light bulbs (now tungsten is preferred). The metal is immune to body liquids and the body tolerates the metal well. Therefore, tantalum has widespread use for surgical use. For instance, it can be used in sutures and as cranial repair plates. The metal is used in the electronics industry for capacitors. The oxide is used to make special glass with a high index of refraction for camera lenses.


 * Estimated Crustal Abundance:** 2.0 milligrams per kilogram
 * Estimated Oceanic Abundance:** 2×10-6 milligrams per liter
 * Number of Stable Isotopes:** 1
 * Ionization Energy:** 7.89 eV




 * Symbol:** Ta **Atomic Number:** 73 **Atomic Mass:** 180.9479 amu **Melting Point:** 2996.0 °C (3269.15 K, 5424.8 °F) **Boiling Point:** 5425.0 °C (5698.15 K, 9797.0 °F) **Number of Protons/Electrons:** 73 **Number of Neutrons:** 108 **Classification:** Transition Metal **Crystal Structure:** Cubic **Density @ 293 K:** 16.654 g/cm3 **Color:** gray

Atomic Structure

 * [[image:http://www.chemicalelements.com/bohr/b0073.gif width="355" height="353"]] ||  || **Number of Energy Levels:** 6
 * First Energy Level:** **Second Energy Level:** **Third Energy Level:** **Fourth Energy Level:** **Fifth Energy Level:** **Sixth Energy Level:** ||

Isotopes

 * ** Isotope ** || ** Half Life ** ||
 * Ta-179 || 1.8 years ||
 * Ta-180 || 1.2E15 years ||
 * Ta-181 || Stable ||
 * Ta-182 || 114.43 days ||

Facts

 * Date of Discovery:** 1802 **Discoverer:** Anders Ekeberg **Name Origin:** After king Tantalus (Greek mythology) **Uses:** capacitors, camera lenses **Obtained From:** tantalite

An example of where to find tantalum would be in natural waters.

Tantalum is also used to produce a variety of alloys that have high melting points, are strong and have good ductility. Alloyed with other metals, it is also used in making carbide tools for metalworking equipment and in the production of superalloys for jet engine components, chemical process equipment, nuclear reactors, and missile parts.[42home][43home] Because of its ductility, tantalum can be drawn into fine wires or filaments, which are used for evaporating metals such as aluminium. Since it resists attack by body fluids and is nonirritating, tantalum is widely used in making surgical instruments and implants. For example, porous tantalum coatings are used in the construction of orthopedic implants due to tantalum's ability to form a direct bond to hard tissue.[44home] Tantalum is inert against most acids except hydrofluoric acid and hot sulfuric acid, also hot alkaline solutions cause tantalum to corrode. This property makes it an ideal metal for chemical reaction vessels and pipes for corrosive liquids. Heat exchanging coils for the steam heating of hydrochloric acid are made from tantalum.[45home] Tantalum was extensively used in the production of ultra high frequency electron tubes for radio transmitters. The tantalum is capable of capturing oxygen and nitrogen by forming nitrides and oxides and therefore helps to sustain the high vacuum needed for the tubes.[19home][45home]