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General Chemistry

Germanium

Definition and meaning of Germanium in chemistry.

Germanium is a hard, grayish-white, lustrous metalloid bearing the chemical symbol Ge and atomic number 32. It is a fundamental semiconductor material that played a highly critical role in the historical development of early solid-state electronics.

In more detail

Positioned in group 14 of the periodic table, germanium exhibits chemical and physical characteristics directly bridging those of true metals and nonmetals, bearing strong behavioral similarities to its immediate group neighbors silicon and tin. It crystallizes with a robust diamond cubic lattice structure and uniquely shares the unusual volumetric property of expanding as it transitions from a liquid state into a solid crystal. In the natural environment, the element is exceedingly rarely found in high concentrations, typically being recovered commercially as a scarce byproduct of sphalerite zinc ores or from the fly ash produced during heavy coal combustion. Germanium compounds primarily exist in the +4 oxidation state in nature, though +2 state compounds are also relatively stable and readily synthesized in laboratory environments. Its exceptional transparency to long-wave infrared radiation makes it a premier optical material for specialized lenses, while its intrinsic electron mobility considerably exceeds that of silicon in certain advanced semiconductor configurations.

Key facts

FieldGeneral Chemistry
SymbolGe
Atomic number32
Atomic mass72.630 u
CategoryMetalloid
State at room temperatureSolid
Melting point938.25 °C (1720.85 °F)
Year discovered1886
Example

Germanium lenses and crystalline windows are incorporated into advanced thermal imaging cameras and military targeting systems because the material is highly transparent to infrared wavelengths.

Frequently asked questions

How was germanium discovered?

It was discovered by Clemens Winkler in the mineral argyrodite, precisely fulfilling the exact elemental properties predicted earlier by Dmitri Mendeleev for an element he called ekasilicon.

Why did silicon replace germanium in most electronics?

Silicon is far more abundant in the Earth's crust, can operate efficiently at higher temperatures without thermal runaway, and forms a highly stable protective oxide layer.

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