Germanium (Ge)
Metalloid · p-block · period 4 · group 14
Hard, brittle, greyish-white lustrous metalloid.
Germanium (symbol Ge) is chemical element number 32, a metalloid in group 14, period 4 of the periodic table. Its standard atomic weight is 72.630 and its electron configuration is [Ar] 3d10 4s2 4p2. At room temperature it is a solid. Predicted by Mendeleev as 'eka-silicon'; its discovery confirmed the periodic table.
Properties
| Atomic number | 32 |
|---|---|
| Atomic mass | 72.630 |
| Category | Metalloid |
| Block | p-block |
| Group · Period | 14 · 4 |
| Electron configuration | [Ar] 3d10 4s2 4p2 |
| Electrons per shell | 2, 8, 18, 4 |
| State at 25 °C | solid |
| Melting point | 1211.4 K |
| Boiling point | 3106 K |
| Density | 5.323 g/cm³ |
| Electronegativity (Pauling) | 2.01 |
| Radioactive | No |
| Origin | primordial |
| Discovered | 1886 · Clemens Winkler |
Key facts about Germanium
- Predicted by Mendeleev as 'eka-silicon'; its discovery confirmed the periodic table.
- The first transistors were made of germanium before silicon took over.
- Transparent to infrared light, so it is used for night-vision and thermal-camera lenses.
- Added to optical fibres to guide the light signal.
What Germanium is used for
Infrared optics, fibre-optic cores, polymerisation catalysts, specialty semiconductors, solar cells.
Where it sits in the periodic table
Germanium is in group 14, period 4, of the p-block. Its electron configuration [Ar] 3d10 4s2 4p2 means its outermost shell holds 4 electrons, which is what places it here and explains much of its chemistry. See Germanium on the interactive table →
Germanium — frequently asked questions
What is Germanium used for?
Infrared optics, fibre-optic cores, polymerisation catalysts, specialty semiconductors, solar cells.
Is Germanium radioactive?
No. Germanium has at least one stable isotope and is not radioactive.
What is the electron configuration of Germanium?
Germanium has the electron configuration [Ar] 3d10 4s2 4p2, which is 2, 8, 18, 4 electrons per shell.
What group and period is Germanium in?
Germanium is in group 14, period 4, in the p-block. Its outer shell holds 4 electrons.
Who discovered Germanium?
Germanium was discovered in 1886 by Clemens Winkler.