n. Symbol Ta
A very hard, dense, gray metallic element that occurs chiefly in columbite-tantalite and is exceptionally resistant to chemical attack below 150°C. It is used to make electrolytic capacitors for portable electronic and computing devices; superalloys for aircraft, missile, and nuclear reactor parts; filaments; and surgical instruments. Atomic number 73; atomic weight 180.948; melting point 3,017°C; boiling point 5,458°C; specific gravity 16.4; valence 2, 3, 4, 5. See Periodic Table.
[New Latin, from Latin Tantalus, Tantalus (from its high resistance to absorbing acids even when immersed in them); see TANTALUS.]
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