Atomic Number: 32 Period Number: 4 Group Number: 14
Germanium is a hard and grayish-white metal in the carbon group. It is active and react with oxygen to form complex in nature. Germanium is mined primarily from sphalerite, silver, lead and copper ores. There are five isotopes of germanium: 70Ge, 72Ge, 73Ge, 74Ge and 76Ge.
Germanium is used as a semiconductor material. It is commonly used, together with silicon, in high speed integrated circuits for improved performance. There is some work being done to replace silicon with germanium in miniaturized chips.It is also used in fluorescent lamps and some LEDs, some guitar effects pedals and solar panels. There are some suggestions that it can be used to support the immune system of cancer patients, but this is still being debated.
Some germanium compounds seem to be effective in killing some types of bacteria and are currently being studied for use in chemotherapy.
Physical and Chemical properties:
Atomic Weight: 72.64
Melting Point: 1211.40 K
Boiling Point: 3106 K
Density: 5.323 g/cm3
Phase at Room Temperature: Solid
Ionization Energy: 7.900 eV
Oxidation States: +4, +2
Wikipedia - Basics on Germanium
WebElements - The basic elements of Germanium
Jefferson Lab - Learning about Germanium