Description
The structure of tantalum is body centered cubic (BCC) metal. It is a refractory metal; stable up to very high temperatures. Tantalum is ductile at room temperature and moderately ductile at cryogenic temperatures. Compton profile of highly pure thin elemental foil of tantalum was investigated using IGP type coaxial photon detector.1
InChI
1S/Ta,GUVRBAGPIYLISA-UHFFFAOYSA-N
InChI Key
GUVRBAGPIYLISA-UHFFFAOYSA-N
Boiling Point
5425 °C (lit.)
Melting Point
2996 °C (lit.)
Density
16.69 g/cm3 (lit.)
Solubility
Insoluble (NIOSH, 2016);Soluble in fused alkalies; insoluble in acids except hydrofluoric and fuming sulfuric acids;Insoluble in water.;Solubility in water: none;Insoluble;
Assay
99.95% trace metals basis
Autoignition Temperature
572 °F
Color Form
Silvery gray metal, body-centered cubic crystal structure;CUBIC OR POWDER;Gray, very hard, malleable, ductile metal;Black powder; steel-blue-colored metal when unpolished, nearly platinum white when polished;Metal: Steel-blue to gray solid or black powder.;
Covalently-Bonded Unit Count
1
Monoisotopic Mass
180.948g/mol
Other Experimental
Atomic number: 73; can readily be drawn in fine wires; valences: 5, also 4, 3, 2.;Two naturally occurring isotopes: 181 (99.99877%); 180 (0.0123%) Half-life: >10+12 years; artificial isotopes: 172-179; 182-186;Specific heat (0 deg C): 0.036 cal/g deg C; Electrical resistivity: (18 deg C): 12.4 microohm-cm;Very resistant to chemical attack; not attacked by aqueous acids other than hydrofluoric; not attacked by aqueous alkalies; slowly attacked by fused alkalies. Reacts with fluorine, chlorine, and oxygen only on heating. At high temperatures absorbs several hundred times its volume of hydrogen; combines with nitrogen, with carbon.;HAS GOOD "GETTERING" ABILITY @ HIGH TEMP;Tensile strength of drawn wire may be as high as 130,000 psi; expansion coefficient 8X10-6 over range 20-1500 deg C; Electrical resistivity: 13.6 microohm-cm @ 0 deg C; 32.0 microohm-cm @ 500 deg C; dust or powder may be flammable.;99.5% pure tantalum is resistant to all concentrations of hot and cold sulfuric acid (except concentrated boiling); hydrochloric acid, nitric and acetic acids, hot and cold dilute sodium hydroxide, all dilutions of hot and cold ammonium hydroxide, mine and seawaters, moist sulfurous atmospheres, aqueous solutions of chlorine;Enthalpy of formation (gas) 782.0 kJ/mol; Heat capacity: 25.4 J/K mol (crystal); 20.9 J/K mol (gas);Thermal conductivity: 0.540 J/cm deg C @ 20 deg C; 0.680 J/cm deg C @ 568 deg C; 0.720 J/cm deg C @ 828 deg C; Enthalpy of fusion: 31,400 J/mol;Maximum valence +5; oxidation states of +4, +3, and +2 are known, but are unstable forms;The dry powder ignites spontaneously in air.;
Topological Polar Surface Area
0A^2
Vapor Pressure
<0.01 mmHg ( 537.2 °C)