Page 7 - Curriculum Visions Dynamic Book

Gd see Gadolinium Germanium (Ge)
Element 32. Germanium, a rare, brittle, silvery-grey metalloid, is in group 4 (the carbon group) in the Periodic Table. Germanium does not readily react with air and so remains lustrous.
Discovery
It was predicted by Dmitri Ivanovich Mendeleev in 1871 and called ekasilicon. It was actually discovered by Clemens Winkler, a German chemist, in 1886.
Technology
Germanium is important as a semi- conductor. It can be doped with arsenic, gallium and other elements to make part of a microprocessor. It is a phosphor in fluorescent lamps and also an alloying agent.The high refractive index of germanium oxide makes it suitable for use in some high-quality wide-angle and microscope lenses. It is also a catalyst.
Geology
Germanium is not found in native form but in germanite, which contains 8% of the element, in argyrodite, a sulphide of germanium and silver, in some zinc ores and in coal. It is obtained from the dusts of zinc smelters and from combustion by-products of coal.
Biology
Germanium does not occur naturally
in the body, but compounds are non-
toxic to people while being poisonous to some bacteria.That makes them potentially valuable as medicines.
Key facts...
Name: germanium
Symbol: Ge
Atomic number: 32
Atomic weight: 72.59
Position in Periodic Table: group 4 (14)
(carbon group); period 4
State at room temperature: solid
Colour: silvery-grey
Density of solid: 5.32 g/cc
Melting point: 937°C
Boiling point: 2,830°C
Origin of name: from the Latin word Germania,
meaning Germany
Shell pattern of electrons: 2–8–18–4
This germanium diode forms part of a circuit.
7