Germanium
Definition and meaning of Germanium in chemistry.
![Germanium element card: symbol Ge, atomic number 32, atomic mass 72.630, electron configuration [Ar] 3d¹⁰ 4s² 4p², oxidation states +4 +2 -4, Metalloid, group 14, period 4, solid at room temperature.](/assets/images/terms/germanium-chemical-element.webp)
Germanium is a hard, shiny, gray-white metalloid with the chemical symbol Ge and atomic number 32. A metalloid is a chemical element that has properties in between metals and nonmetals. This important element helped scientists build the very first digital electronics.
In more detail
Germanium sits in group 14 of the periodic table, showing chemical behavior similar to silicon and tin. The solid element forms a strong crystal structure that expands slightly when freezing into a solid. Water and silicon are among the very few other substances that display this structural property.
You will rarely find pure germanium in nature because it is widely scattered in trace amounts. Mining companies usually find it mixed into zinc ores, or they extract it from coal ash. In chemical compounds, germanium usually takes a stable +4 oxidation state under normal conditions.
However, scientists can also make less stable compounds with a +2 oxidation state in the laboratory. A common student misconception is that silicon has always been the main semiconductor for computer chips. In reality, the very first electrical transistors ever built relied entirely on high-purity germanium.
Germanium lets long infrared heat waves pass right through it, making it ideal for specialized lenses. It also moves electrons much faster than silicon does in many high-speed electrical circuits. Many modern solar cells use a thin layer of germanium to capture extra sunlight. This helps convert solar energy into electrical power with much higher efficiency than standard panels.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Ge |
| Atomic number | 32 |
| Atomic mass | 72.630 u |
| Category | Metalloid |
| Melting point | 938.25 °C (1720.85 °F) |
| Year discovered | 1886 |
Engineers use germanium to make special lenses and windows for thermal imaging cameras. These cameras work by detecting heat waves instead of visible light to see in total darkness. The cameras work well because germanium lets infrared heat waves pass through without blocking them.
Frequently asked questions
How was germanium discovered?
Clemens Winkler found germanium in a mineral called argyrodite in 1886. It perfectly matched properties predicted by Dmitri Mendeleev.
Why did silicon replace germanium in most electronics?
Silicon is much more common in the Earth's crust and costs less to refine. It also operates much better at high temperatures without failing.
Why is germanium used in thermal cameras instead of normal glass?
Standard glass blocks infrared radiation, which is the light wavelength that carries heat. Germanium is completely transparent to these heat waves.
Related terms
Sources & references
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