- Elements List
- Aluminium, Al
- Antimony, Sb
- Arsenic, As
- Barium, Ba
- Beryllium, Be
- Bismuth, Bi
- Boron, B
- Cadmium, Cd
- Calcium, Ca
- Carbon, C (Graphite)
- Cerium, Ce
- Cesium, Cs
- Chromium, Cr
- Cobalt, Co
- Copper, Cu
- Dysprosium, Dy
- Erbium, Er
- Europium, Eu
- Gadolinium, Gd
- Gallium, Ga
- Germanium, Ge
- Gold, Au
- Hafnium, Hf
- Holmium, Ho
- Indium, In
- Iridium, Ir
- Iron, Fe
- Lanthanum, La
- Lead, Pb
- Lithium, Li
- Lutetium, Lu
- Magnesium, Mg
- Manganese, Mn
- Mercury, Hg
- Molybdenum, Mo
- Neodymium, Nd
- Nickel, Ni
- Niobium, Nb
- Osmium, Os
- Palladium, Pd
- Phosphorus, P
- Platinum, Pt
- Potassium, K
- Praseodymium, Pr
- Rhenium, Re
- Rhodium, Rh
- Rubidium, Rb
- Ruthenium, Ru
- Samarium, Sm
- Scandium, Sc
- Selenium, Se
- Silicon, Si
- Silver, Ag
- Sodium, Na
- Strontium, Sr
- Sulphur, S
- Tantalum, Ta
- Tellurium, Te
- Terbium, Tb
- Thallium, Tl
- Thorium, Th
- Thulium, Tm
- Tin, Sn
- Titanium, Ti
- Tungsten, W
- Vanadium, V
- Ytterbium, Yb
- Yttrium, Y
- Zinc, Zn
- Zirconium, Zr
Tantalum, Ta
Description
Tantalum is a chemical element with the symbol Ta and atomic number 73. A rare, hard, blue-gray, lustrous, transition metal, tantalum is highly corrosion-resistant and occurs naturally in the mineral tantalite.
Tantalum is dark, dense, ductile, very hard, easily fabricated, and highly conductive of heat and electricity. The metal is renowned for its resistance to corrosion by acids; in fact, at temperatures below 150 °C tantalum is almost completely immune to attack by the normally aggressive aqua regia. It can be dissolved with hydrofluoric acid or acidic solutions containing the fluoride ion and sulfur trioxide, as well as with a solution of potassium hydroxide. Tantalum's high melting point of 3017 °C (boiling point 5458 °C) is exceeded only by tungsten and rhenium for metals, and carbon.
Available Forms:
| Technical Data | ||||||||
| Symbol | Ta | Density (20°C)/gcm-3 | 16.65 | |||||
| Atomic number | 73 | Melting point /°C | 2980 | |||||
| No. of naturally occurring isotopes | 2 | Boiling point /°C | 5534 | |||||
| Atomic weight | 180.9479 | ΔHfus/kJmol-1 | 24.7 | |||||
| Electronic configuration | [Xe]4f145d36s2 | ΔHvap/kJmol-1 | 758.2 | |||||
| Metal radius(12-coordinate)/pm | 146 | ΔHf(monoatomic gas)/kJmol-1 | 782(+/-6) | |||||
| Ionic radius(6-coordinate)/pm V | 64 | Electrical resistivity | ||||||
| Ionic radius(6-coordinate)/pm IV | 68 | (20°C)/μohm cm | -12.4 | |||||
| Ionic radius(6-coordinate)/pm III | 72 | Electronegativity χ | 1.5 | |||||
| Evaporation Techniques | ||||||||
| Temperature (oC) @Vap. Pressure | Techniques | Remarks | ||||||
| 10-8 Torr | 10-6 Torr | 10-4 Torr | Electron Beam | Crucible | Coil | Boat | ||
| 1960 | 2240 | 2590 | Excellent | - | - | - | Forms good films Go to Evaporation Sources Page | |
Unit 12, Hassocks Wood, Basingstoke, Hampshire, RG24 8UQ, UK. High Purity Materials For Research, Development and Industry
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