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Tantalum

element with the atomic number of 73

Tantalum is a chemical element. Tantalum was named tantalium. It has the chemical symbol Ta. It has the atomic number 73. It is a rare metal. It is hard and blue-gray. In chemistry it is placed in a group of metal elements named the transition metals.

Tantalum,  73Ta
Tantalum single crystal and 1cm3 cube.jpg
General properties
Pronunciation/ˈtæntələm/ (TAN-təl-əm)
Appearancegray blue
Standard atomic weight (Ar, standard)180.94788(2)[1]
Tantalum in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Nb

Ta

Db
hafniumtantalumtungsten
Atomic number (Z)73
Groupgroup 5
Periodperiod 6
Blockd-block
Element category  transition metal
Electron configuration[Xe] 4f14 5d3 6s2
Electrons per shell
2, 8, 18, 32, 11, 2
Physical properties
Phase at STPsolid
Melting point3290 K ​(3017 °C, ​5463 °F)
Boiling point5731 K ​(5458 °C, ​9856 °F)
Density (near r.t.)16.69 g/cm3
when liquid (at m.p.)15 g/cm3
Heat of fusion36.57 kJ/mol
Heat of vaporization753 kJ/mol
Molar heat capacity25.36 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 3297 3597 3957 4395 4939 5634
Atomic properties
Oxidation states−3, −1, +1, +2, +3, +4, +5 (a mildly acidic oxide)
ElectronegativityPauling scale: 1.5
Ionization energies
  • 1st: 761 kJ/mol
  • 2nd: 1500 kJ/mol
Atomic radiusempirical: 146 pm
Covalent radius170±8 pm
Color lines in a spectral range
Spectral lines of tantalum
Other properties
Natural occurrenceprimordial
Crystal structurebody-centered cubic (bcc)[2]
Body-centered cubic crystal structure for tantalum

α-Ta
Crystal structuretetragonal[2]
Tetragonal crystal structure for tantalum

β-Ta
Speed of sound thin rod3400 m/s (at 20 °C)
Thermal expansion6.3 µm/(m·K) (at 25 °C)
Thermal conductivity57.5 W/(m·K)
Electrical resistivity131 nΩ·m (at 20 °C)
Magnetic orderingparamagnetic[3]
Magnetic susceptibility+154.0·10−6 cm3/mol (293 K)[4]
Young's modulus186 GPa
Shear modulus69 GPa
Bulk modulus200 GPa
Poisson ratio0.34
Mohs hardness6.5
Vickers hardness870–1200 MPa
Brinell hardness440–3430 MPa
CAS Number7440-25-7
History
DiscoveryAnders Gustaf Ekeberg (1802)
Recognized as a distinct element byHeinrich Rose (1844)
Main isotopes of tantalum
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
177Ta syn 56.56 h ε 177Hf
178Ta syn 2.36 h ε 178Hf
179Ta syn 1.82 y ε 179Hf
180Ta syn 8.125 h ε 180Hf
β 180W
180mTa 0.012% stable
181Ta 99.988% stable
182Ta syn 114.43 d β 182W
183Ta syn 5.1 d β 183W
| references
Tantalum in a glass tube

Tantalum does not easily corrode. It is found in the mineral tantalite.

SourcesEdit

  1. Meija, J.; Coplen, T. B.; Berglund, M.; Brand, W.A.; De Bièvre, P.; Gröning, M.; Holden, N.E.; Irrgeher, J. et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry 88 (3): 265-91. doi:10.1515/pac-2015-0305. https://www.degruyter.com/downloadpdf/j/pac.2016.88.issue-3/pac-2015-0305/pac-2015-0305.xml. 
  2. 2.0 2.1 Moseley, P. T.; Seabrook, C. J. (1973). "The crystal structure of β-tantalum". Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry 29 (5): 1170–1171. doi:10.1107/S0567740873004140. 
  3. Lide, D. R., ed. (2005). "Magnetic susceptibility of the elements and inorganic compounds". CRC Handbook of Chemistry and Physics (PDF) (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.
  4. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.