Tantalum
73
Ta
Group
5
Period
6
Block
d
Protons
Electrons
Neutrons
73
73
108
General Properties
Atomic Number
73
Atomic Weight
180.94788
Mass Number
181
Category
Transition metals
Color
Gray
Radioactive
No
Named after Tantalos, a Greek mythological character, father of Niobe
Crystal Structure
Body Centered Cubic
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.
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.
Electrons per shell
2, 8, 18, 32, 11, 2
Electron Configuration
[Xe] 4f14 5d3 6s2
Tantalum occurs principally in the mineral columbite-tantalite
Physical Properties
Phase
Solid
Density
16.654 g/cm3
Melting Point
3290.15 K | 3017 °C | 5462.6 °F
Boiling Point
5731.15 K | 5458 °C | 9856.4 °F
Heat of Fusion
36 kJ/mol
Heat of Vaporization
735 kJ/mol
Specific Heat Capacity
0.14 J/g·K
Abundance in Earth's crust
0.00017%
Abundance in Universe
8×10-9%
CAS Number
7440-25-7
PubChem CID Number
23956
Atomic Properties
Atomic Radius
146 pm
Covalent Radius
170 pm
Electronegativity
1.5 (Pauling scale)
Ionization Potential
7.5496 eV
Atomic Volume
10.90 cm3/mol
Thermal Conductivity
0.575 W/cm·K
Oxidation States
-1, 2, 3, 4, 5
Applications
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.
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.
Tantalum is considered to be non-toxic
Isotopes
Stable Isotopes
181TaUnstable 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, 180Ta, 182Ta, 183Ta, 184Ta, 185Ta, 186Ta, 187Ta, 188Ta, 189Ta, 190Ta