Germanium
Germanium (jer-MAY-ni-em) is a brittle, silvery-white semi-metal (metalloid).[1]
| Germanium | |
|---|---|
| Properties | |
| Atomic symbol | Ge |
| Atomic number | 32 |
| Classification | Group IVA, Carbon family |
| Atomic mass | 72.59 |
| Number of Stable Isotopes | 70, 72, 73, 74, 76 |
| Number of Unstable Isotopes | 66, 67, 68, 69, 71, 75, 77, 78 |
| Melting point (°C) | 937.4 (1,720.85 °F) |
| Boiling point (°C) | 2,830 (5,131 °F) |
| Density (grams per cc) | 5.323 |
| Hardness (Moh's scale) | 6.25 |
| Abundance in lithosphere (%) | 0.0007 |
| Oxidation states | +2, +4 |
| Other Information | |
| Date of discovery | 1886 |
| Name of discoverer | Clemens Winkler |
| Name origin | From the Latin word Germania, Germany |
| Uses | Semiconductors |
| Obtained from | Refining of copper, zinc, lead |
History
Germanium was first proposed to exist by Dmitri Mendeleyev in 1871. He had recently created a Periodic Table of Elements, and identified gaps which where unknown elements. Germanium was officially discovered in 1886 by Clemens Winkler, a German chemist. He found it in the mineral argyrodite (Ag8GeS6).
Uses
Germanium is primarily used as a semiconductor. With arsenic, gallium, indium, antimony or phosphorus, it is used to make transistors. Another major use for Germanium is lenses. It is used in the manufacture of wide-angle camera lenses and objective lenses for microscopes.[2] It is also used to create alloys and as a phosphor in fluorescent lamps.[3] Additionally, adding 1% germanium to silver prevents tarnishing.[4]