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Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust. It is widely distributed throughout space in cosmic dusts , planetoids , and planets as various forms of silicon dioxide (silica) or silicates .
Naturally occurring silicon is found in silicate and aluminosilicate minerals. One of the most common silicon compounds found in the Earth's crust is silicon dioxide or silica, which often occurs as quartz. Organosilicon compounds are fairly stable due to the similarity in strength of the Si–C bond to the C–C bond.
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula SiO 2, commonly found in nature as quartz. [5] [6] In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product.
Chalcedony has a waxy luster, and may be semitransparent or translucent. It can assume a wide range of colors, but those most commonly seen are white to gray, grayish-blue or a shade of brown ranging from pale to nearly black. The color of chalcedony sold commercially is often enhanced by dyeing or heating. [4]
It is commonly found within the margins of rhyolitic lava flows known as obsidian flows. These flows have a high content of silica , giving them a high viscosity . The high viscosity inhibits diffusion of atoms through the lava, which inhibits the first step ( nucleation ) in the formation of mineral crystals .
Zeolite exhibited in the Estonian Museum of Natural History. Zeolite is a family of several microporous, crystalline aluminosilicate materials commonly used as commercial adsorbents and catalysts. [1] They mainly consist of silicon, aluminium, oxygen, and have the general formula M n+ 1/n (AlO 2) − (SiO 2) x ･y H 2 O where M n+ 1/n is ...
In mineralogy, silica (silicon dioxide, SiO 2) is usually considered a silicate mineral rather than an oxide mineral. Silica is found in nature as the mineral quartz , and its polymorphs . On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working ...
A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).