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 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance


Name: Tantalum Symbol: Ta
Group: Trans. Met. Atomic weight: 180.947
Density @ 293 K: 16.6 g/cm3 Atomic volume: 10.90 cm3/mol
Group: Trans. Met. discovered: 1802


state (s, l, g): s
melting point: 3269.2 K boiling point: 5807 K
Heat of fusion: 31.60 kJ/mol Heat of vaporization: 743.0 kJ/mol


1st ionization energy: 761 kJ/mole
electronegativity: 1.5 2nd ionization energy: kJ/mole
electron affinity: 31.1 kJ/mole 3rd ionization energy: kJ/mole
Specific heat: 0.14 J/gK heat atomization: 782 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,32,11,2 electron configuration: [Xe] 4f14 5d3 6s2
minimum oxidation number: -1 maximum oxidation number: 5
min. common oxidation no.: 0 max. common oxidation no.: 5

Appearance & Characteristics:

structure: bcc: body-centered cubic color: gray
uses: surg. implants,heat exch. toxicity:
hardness: mohs characteristics: hard, inert at <100 deg.C


reaction with air: none
reaction with 6M HCl: none reaction with 6M HCl: none
reaction with 15M HNO3: none reaction with 6M NaOH: none

Other Forms:

number of isotopes: 2 hydride(s): TaH
oxide(s): TaO2 Ta2O5 chloride(s): TaCl3 TaCl4 TaCl5


ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: 146 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): 86 pm


thermal conductivity: 57.5 J/m-sec-deg
electrical conductivity: 80.321 1/mohm-cm polarizability: 13.1 A^3


source: Tantalite (oxide)
rel. abund. solar system: -1.684 log abundance earth's crust: 0.3 log
cost, pure: 120 $/100g cost, bulk: $/100g