The Element Germanium
[Click for Isotope Data]
Atomic Number: 32
Atomic Weight: 72.630
Melting Point: 1211.40 K (938.25°C or 1720.85°F)
Boiling Point: 3106 K (2833°C or 5131°F)
Density: 5.323 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Semi-metal
Period Number: 4 Group Number: 14 Group Name: none
What's in a name? Named for the country of Germany.
Say what? Germanium is pronounced as jer-MAY-ni-em.
History and Uses:
First proposed to exist by Dmitri Mendeleyev in 1871 based on gaps in his newly created Periodic Table of Elements, germanium was discovered by the German chemist Clemens Winkler in the mineral argyrodite (Ag8GeS6) in 1886. Today, germanium is primarily obtained from the smelting of zinc ores and from the byproducts of burning certain types of coal.
The largest use of germanium is in the semiconductor industry. When doped with small amounts of arsenic, gallium, indium, antimony or phosphorus, germanium is used to make transistors for use in electronic devices. Germanium is also used to create alloys and as a phosphor in fluorescent lamps. Both germanium and germanium oxide (GeO) are transparent to infrared radiation and are used in infrared optical instruments and infrared detectors. Some germanium compounds seem to be effective in killing some types of bacteria and are currently being studied for use in chemotherapy.
Estimated Crustal Abundance: 1.5 milligrams per kilogram
Estimated Oceanic Abundance: 5×10-5 milligrams per liter
Number of Stable Isotopes: 5 (View all isotope data)
Ionization Energy: 7.900 eV
Oxidation States: +4, +2
3s2 3p6 3d10