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Sunday, June 19, 2016

Tantalum chemical element

Tantalum was discovered by Anders Gustaf Ekeberg in 1802.
The chemical symbol for Tantalum is Ta and its atomic number is 73.
We find it listed in the periodic table of elements in group 5 and 6 period and block d.
Tantalum belongs to the family of transition metals such as for example the Silver, the Bohrium, cadmium, ...
This element is stable.


Tantalum chemical element


Tantalum Atomic number (Z) 73
Group, block group 5, d-block
Period: period 6
Element categorytransition metal
Standard atomic weight (±) (Ar) 180.94788(2).
Electron configuration:  [Xe] 4f14 5d3 6s2
per shell 2, 8, 18, 32, 11, 2

Tantalum Physical properties
Phase: solid
Melting point: 3290 K ​(3017 °C, ​5463 °F)
Boiling point: 5731 K ​(5458 °C, ​9856 °F)
Density near r.t. : 16.69 g/cm3
when liquid, at m.p. 15 g/cm3
Heat of fusion 36.57 kJ/mol
Heat of vaporization: 753 kJ/mol
Molar heat capacity: 25.36 J/(mol·K)

Tantalum Atomic properties
Oxidation states: 5, 4, 3, 2, 1, −1, −3 ​(a mildly acidic oxide)
Electronegativity: Pauling scale: 1.5
Ionization energies: 1st: 761 kJ/mol
2nd: 1500 kJ/mol
Atomic radius empirical: 146 pm
Covalent radius: 170±8 pm

Tantalum Crystal structure: ​body-centered cubic
Crystal structure: ​tetragonal Tetragonal crystal structure for tantalum
Speed of sound thin rod 3400 m/s (at 20 °C)
Thermal expansion 6.3 µm/(m·K) (at 25 °C)
Thermal conductivity: 57.5 W/(m·K)
Electrical resistivity: 131 nΩ·m (at 20 °C)
Magnetic ordering paramagnetic.
Young's modulus: 186 GPa
Shear modulus 69 GPa
Bulk modulus :200 GPa
Poisson ratio: 0.34
Mohs hardness: 6.5
Vickers hardness: 870–1200 MPa
Brinell hardness: 440–3430 MPa
CAS Number :7440-25-7