| Atomic Atomic Mass: 183.85 |
Successive Ionization Energies: |
| Electronegativity: |
W -› W + : 770 kJ mol-1 |
| Pauling: 2.36 |
W+1 -› W+2 : (1700) kJ mol-1 |
| Allred: 1.4 |
W+2 -› W+3 : (2300) kJ mol-1 |
| Absolute: 4.4 eV |
W+3 -› W+4 : (3400) kJ mol-1 |
| Electron Affinity: 78.6 kJ mol-1 |
W+4 -› W+5 : (4600) kJ mol-1 |
| Polarizability: 11.1 Å3 |
W+5 -› W+6 : (5900) kJ mol-1 |
| Effective Nuclear Charge: |
Common Ions |
| Slater: 4.35 |
|
| Clementi: 9.85 |
|
| Froese Fischer: 14.22 |
|
| Radius: |
|
| W 4 +: 68 pm |
|
| W 6 +: 62 pm |
|
| Atomic: 137 pm |
|
| Covalent: 130 pm |
|
The metal is obtained commercially be recucing tungsten oxide with hydrogen or carbon. Pure tungsten is a stelel-gray to tin-white metal. Very pure tungsten can be cut with a hacksaw, and can be forged, spun, drawn, and extruded. The impure metal is brittle and can be worked only with difficulty. Tungsten has the highest melting point of all metals, and at temperatures over 1650C has the highest tensile strength. The metal oxidizes in air and must be protected at elevated temperatures.It has excellent corrosion resistance and is attacked only slightly by most mineral acids.
|
