Ge
Germanium is a metalloid semiconductor predicted by Mendeleev and used in early transistors.
Physical Properties
| Atomic Mass | 72.63 u |
| Density | 5.323 g/cm³ |
| Melting Point | 1211.4 K |
| Boiling Point | 3106.0 K |
| Appearance | Grayish-white metallic |
| State at Room Temp | Solid |
Chemical Properties
| Electronegativity | 2.01 (Pauling) |
| 1st Ionization Energy | 762.0 kJ/mol |
| Electron Affinity | 119.0 kJ/mol |
| Oxidation States | -4, +1, +2, +3, +4 |
Atomic Properties
| Electron Configuration | [Ar] 3d10 4s2 4p2 |
| Atomic Radius | 122.0 pm |
| Covalent Radius | 120.0 pm |
| Van der Waals Radius | 211.0 pm |
Discovery
| Discovered By | Clemens Winkler |
| Discovery Year | 1886 |
| Location | Freiberg, Germany |
| Named After | Latin 'Germania' meaning Germany |
About Germanium
Germanium is a lustrous, hard, grayish-white metalloid predicted by Mendeleev as 'eka-silicon.' It was the semiconductor in the first transistors and is transparent to infrared radiation.
Uses & Applications
Fiber optic systems, infrared optics, polymerization catalysts, solar cells, and semiconductors.
Fun Fact
Germanium was predicted by Mendeleev 15 years before its discovery, with remarkably accurate predictions of its properties.
Isotopes
| Mass Number | Abundance | Half-Life | Stable |
| 70 | 0.2038% | - | Yes |
| 72 | 0.2731% | - | Yes |
| 73 | 0.0776% | - | Yes |
| 74 | 0.3672% | - | Yes |
Electron Configuration
[Ar] 3d10 4s2 4p2