Stable isotope Tantalum (Ta)

Isotope Z(p) N(n) Atomic Mass Natural Abundance Enrichment Level Chemical Form
Ta-180 73 107 179.947466 0.012% 0.26-5.70% Oxide
Ta-181 73 108 180.947996 99.988% 99.99% Oxide

Properties of Tantalum

Name Tantalum
Symbol Ta
Atomic number 73
Atomic weight 180.95
Standard state Solid at 298 ºK
CAS Registry ID 7440-25-7
Group in periodic table 5
Group name None
Period in periodic table 6
Block in periodic table d-block
Color Gray blue
Classification Metallic
Melting point 2996 °C
Boiling point 5425 °C
Vaporization point 5458 ºC
Thermal conductivity 57.5 W/(m·K) at 298.2 °K
Electrical resistivity 12.45 µΩ·cm at 0 °C
Electronegativity 1.5
Specific heat 0.14 kJ/kg K
Heat of vaporization 735 kJ·mol-1
Heat of fusion 36 kJ·mol-1
Density of liquid 15 g/cm3
Density of solid 16.65 g/cm3
Electron configuration [Xe]4f145d36s2
Atomic radius 1.46 Å
Ionic radius Ta5+: 0.64 Å (coordination number 6)
Oxidation state +5