Tantalum

Tantalum (Ta)

Heavy blue-grey metallic transition element. Ta-181 is a stable isotope, and Ta-180 is a radioactive isotope, with a half-life in excess of 10^7 years. Used in surgery as it is unreactive. Forms a passive oxide layer in air. Identified in 1802 by Ekeberg and isolated in 1820 by Jons J. Berzelius.
Atomic Number73
Atomic Weight180.94788
Mass Number181
Group5
Period6
Blockd
Protons73 p+
Neutrons108 n0
Electrons73 e-
Tantalum single crystal and 1cm3 cube.jpg Animated Bohr Model Enhanced Bohr Model Bohr Model Orbital Diagram

Properties

Atomic Radius
145 pm
Atomic Volume
Covalent Radius
146 pm
Metallic Radius
134 pm
Ionic Radius
72 pm
Crystal Radius
86 pm
Van der Waals radius
222.00000000000003 pm
Density
16.4 g/cm³
Boiling Point
5,698 K
Melting Point
3,269 K
Electrons per shell2, 8, 18, 32, 11, 2
Electronegativity
1.5
Electrophilicity
1.0716190618856 eV/particle
Proton Affinity
Electron Affinity
Ionization Potential
7.54957 eV/particle
Heat of Vaporization
758 kJ/mol
Heat of Fusion
24.7 kJ/mol
Heat of Formation
782 kJ/mol
Molar Heat Capacity
25.36 J/(mol K)
Specific Heat Capacity
Thermal Conductivity
57.5 W/(m K)
Gas Basicity
Dipole Polarizability
74 a₀
C6 Dispersion Coefficient
Oxidation States-1, 2, 3, 4, 5
Color
Gray
Crystal StructureBody Centered Cubic (BCC)
Lattice Constant
3.31 Å
Bulk Modulus
Electrical Resistivity
Electron Configuration[Xe] 4f14 5d3 6s2
Magnetic Ordering
Magnetic Susceptibility
PhaseSolid
Poisson Ratio
Shear Modulus
Young's Modulus
Allotropes
Alternate Names
Adiabatic Index
Appearance
Electric Conductivity
Critical Pressure
Critical Temperature
Curie Point
Electrical
Hardness
Magnetic Susceptibility
Magnetic
Neel Point
Neutron Cross Section
Neutron Mass Absorption
Gas Phase
Quantum Numbers
Refractive Index
Space Group
Speed of Sound
Superconducting Point
Thermal Expansion
Valence Electrons
Classification
CategoryTransition metals, Transition metals
CAS GroupVA
IUPAC GroupVB
Glawe Number52
Mendeleev Number49
Pettifor Number53
Geochemical Classhigh field strength
Goldschmidt Classlitophile
Radioactivity
RadioactiveNo
Decay Mode
Half-Life
Lifetime
Abundance
Abundance in Earth's crust
Abundance in Oceans
0.000002 mg/L
Abundance in Human Body
Abundance in Meteor
Abundance in Sun
Abundance in Universe8×10-9%

Isotopes of Tantalum

Stable Isotopes
180Ta 181Ta
Unstable Isotopes
155Ta 156Ta 157Ta 158Ta 159Ta 160Ta 161Ta 162Ta 163Ta 164Ta 165Ta 166Ta 167Ta 168Ta 169Ta 170Ta 171Ta 172Ta 173Ta 174Ta 175Ta 176Ta 177Ta 178Ta 179Ta 182Ta 183Ta 184Ta 185Ta 186Ta 187Ta 188Ta 189Ta 190Ta

History

Tantalum was discovered in Sweden in 1802 by Anders Ekeberg in the minerals tantalite from Finland and yttrotantalite from Sweden. Unfortunately, William Hyde Wollaston claimed Ekeberg's new element was actually niobium, which had also been discovered in 1802. In 1846, German chemist Heinrich Rose finally proved beyond doubt that tantalum and niobium were different elements. Named after Tantalos, a Greek mythological character, father of Niobe

DiscoverersAnders Ekeberg
Discovery LocationSweden
Discovery Year1802
Name OriginFrom king Tantalus of Greek mythology, father of Niobe.
Tantalum is considered to be non-toxic
Tantalum occurs principally in the mineral columbite-tantalite

Uses

Tantalum is used in the electronics industry for capacitors and high power resistors. The high melting point and oxidation resistance lead to the use of the metal in the production of vacuum furnace parts. Tantalum oxide is used to make special glass with high index of refraction for camera lenses. Often used as an economical substitute for platinum. Tantalum pentoxide is used in capacitors and in camera lenses to increase refracting power. It and its alloys are corrosion and wear resistant so it is used to make surgical and dental tools.

Sources

Chiefly occurs in the mineral tantalite. Always found with niobium.