|Atomic mass||72.59 amu|
Germanium resembles silicon.
Like silicon, germanium is used as semiconductors, especially in transistors. For this purpose, exceedingly high purity is essential. Germanium chloride is purified by fractional distillation and is roasted in oxygen to produce germanium oxide, GeO2. It is then reacted with hydrogen in a hot tube or on a hot wire. Then by a process called "zone refining", super-pure germanium is obtained.
Germanium has replaced large vacuum tubes with electronic devices called semiconductors. Other uses of germanium include infrared spectrometer windows and lenses.