Technical data for Tantalum

Overview
NameTantalum
SymbolTa
Atomic Number73
Atomic Weight180.9479
Density16.65 g/cm3
Melting Point3017 °C
Boiling Point5458 °C

Thermal properties
PhaseSolid
Melting Point3017 °C
Boiling Point5458 °C
Absolute Melting Point3290 K
Absolute Boiling Point5731 K
Heat of Fusion36 kJ/mol
Heat of Vaporization735 kJ/mol
Heat of CombustionN/A
Specific Heat140 J/(kg K)[note]
Thermal Conductivity57 W/(m K)
Thermal Expansion6.3×10-6 K-1

Bulk physical properties
Density16.65 g/cm3
Density (Liquid)15 g/cm3
Molar Volume0.0000108677
Brinell Hardness800 MPa
Mohs Hardness6.5 MPa
Vickers Hardness873 MPa
Bulk Modulus200 GPa
Shear Modulus69 GPa
Young Modulus186 GPa
Poisson Ratio0.34
Speed of Sound3.4×103 m/s
Thermal Conductivity57 W/(m K)
Thermal Expansion6.3×10-6 K-1

Reactivity
Valence5
Electronegativity1.5
ElectronAffinity31 kJ/mol
Ionization Energies
761, 1.5×103 kJ/mol

Health and Safety
Autoignition PointN/A
FlashpointN/A

Classifications
Alternate NamesNone
Nams of AllotropesNone
Blockd
Group5
Period6
Electron Configuration[Xe]4f145d36s2
ColorGray
Discovery
1802 in Sweden
Gas phaseN/A
CAS NumberCAS7440-25-7

Electrical properties
Electrical TypeConductor
Electrical Conductivity7.7×106 S/m
Resistivity1.3×10-7 m Ω
Superconducting Point4.47

Magnetic properties
Magnetic TypeN/A
Curie PointN/A
Mass Magnetic Susceptibility1.07×10-8
Molar Magnetic Susceptibility1.936×10-9
Volume Magnetic Susceptibility0.0001782

Abundances
% in Universe8×10-9%
% in SunN/A
% in Meteorites2×10-6%
% in Earth's Crust0.00017%
% in Oceans2×10-10%
% in HumansN/A

Atomic dimensions and structure
Atomic Radius200 pm
Covalent Radius138 pm
Van der Waals RadiusN/A
Crystal StructureBody Centered Cubic
Lattice Angles
π/2, π/2, π/2
Lattice Constants
330.13, 330.13, 330.13 pm
Space Group NameIm_ 3m
Space Group Number229

Nuclear Properties
Half-LifeStable
LifetimeStable
Stable Isotopes
181Ta
Isotopic Abundances
181Ta99.988%

Notes on the properties of Tantalum:
Specific Heat: Value given for solid phase.