Tantalum

Symbol: Ta
Atomic number: 73
Category: transition metals
Group: 5
Period: 6
Block: d
Atomic weight: 180.94788 g/mol
Electrons per shell: 2, 8, 18, 32, 11, 2
CAS number: 7440-25-7
Phase: solid
Density: 16.69 kg/dm3 (near room temperature)
Melting point: 3290 K (3017 °C, 5463 °F)
Boiling point: 5731 K (5458 °C, 9856 °F)
Crystal structure: cubic body centered
Oxidation states: 5, 4, 3
Electronegativity: 1.5 (Pauling scale)
Name's origin: Tantalus
Name's meaning: the father of the goddess Niobe in Greek mythology
Facts:
- many contemporary chemists believed niobium and tantalum were the same elements until 1844
- is dark, dense, ductile, very hard, easily fabricated, and highly conductive of heat and electricity
- is highly corrosion-resistant and occurs naturally in the mineral tantalite
- its main use today is in tantalum capacitors, but it's also used in laboratory equipment