Germanium (Ge)
Germanium (Ge) is element 32, a metalloid. Atomic mass 72.63, configuration [Ar] 3d¹⁰ 4s² 4p². Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 32 |
|---|---|
| Symbol | Ge |
| Standard atomic weight | 72.630(8) |
| Category | Metalloid |
| Group | 14 |
| Period | 4 |
| State at room temperature | Solid |
| Electron configuration | [Ar] 3d¹⁰ 4s² 4p² |
| Valence electrons | 4 |
| Common oxidation states | -4, +2, +4 |
| Common ions | No common ions |
| Electronegativity (Pauling) | 2.01 |
| First ionization energy | 762 kJ/mol |
| Electron affinity | 118.9 kJ/mol |
| Atomic radius | 125 pm |
| Density | 5.323 g/cm³ |
| Melting point | 938.3°C |
| Boiling point | 2833°C |
| Specific heat | 0.32 J/(g·°C) |
Natural isotopes
- Ge-70: Stable
- Ge-72: Stable
- Ge-73: Stable
- Ge-74: Stable
Common uses
- Fiber optics
- Infrared optics
- Polymerization catalysts
Where it matters
- Electronics history (First transistors were Ge)
- Fiber optics
Hazards
- Some organic compounds toxic
History
| Discovered | 1886 |
|---|---|
| Discovered by | Clemens Winkler |
| Name | Winkler (Germania/Germany) |