Germanium

Germanium is an element of the fourth group of the Periodic System. Atomic number is 32, element atomic weight is 72, 59. It was named after homeland of K.A.Vinkler - Germany. This element refers to the scattered. In nature it does not occur in free form but only as an impurity in the sediments, nickel, and tungsten ores in silicates, coal, thermal waters, peat and seaweed. 
Germanium was discovered in 1886 by A.Vinkler. 

Physical and chemical properties of germanium: 
Germanium is a silvery metal with a metallic luster. Germanium is quite brittle and does not undergo hot and cold working pressure up to 550 ° C. If the temperature is higher than 550°C the metal becomes malleable. Germanium is quite resistant to water, air, hydrochloric acid, it weakly reacts with solutions of caustic alkalis and is rapidly oxidized in air. 

Germanium is produced by processing using by-products, burning coal ash, nonferrous metals and steel ore, etc. In metallurgical process germanium is extracted at a temperature of from 800 to 1800 ° C. For technical germanium in quartz columns hydrochloric acid is purified by extraction, thermal diffusion aimed fro crystallization, and other methods. Germanium is identified by using emission spectral analysis. Also it is possible to identify it by color reactions. For example, if the color is bright yellow it is a molybdenici-acid germanium. 

Germanium is a chemical compound usually has the valence of 2 or 4. If the valence is 4 then chemical compounds are more stable. Under regular conditions germanium is resistant to water and air, acids and alkalis, and is easily soluble in an alkaline solution of hydrogen peroxide and aqua regia. Alloys of this element are applied with the basis of germanium dioxide.

The usage of germanium: 
Germanium is a semiconductor material used in the form of high-frequency single crystals for the manufacture of transistors, diodes, photoresistor and photodiodes. Hall sensors, lenses, X-ray spectroscopy, resistance thermometers, etc are manufacture from its element. In the dental and jewelry techniques this element is also widely used due to high hardness and strength. Some germanium alloys are used as solders anticorrosion coatings. 

A single-crystal germanium. Specification and State Standard 16153-80 is defined by standard and applies to single-crystal ingot of germanium, which is used in the manufacture of semiconductor devices, and establishes requirements for single-crystal germanium made of economy requirement. 

The impurities of germanium dioxide are applied in alloys used in the rolled metal for the manufacture of wire, sheet, rod, etc.