![]() ![]() In 1808, Sir Humphry Davy named this hypothetical element “silicium”, combining the Latin silex, meaning stone, with the traditional -ium ending often given to metallic elements. It was first proposed that silica sand was likely the oxide of a previously unknown element by Antoine Lavoisier in 1787. Instead, it occurs mostly as silicon dioxide, more commonly known as sand or quartz, or in silicate minerals, generally in the found in the forms of clay or rock. Silicon is truly ubiquitous, but is almost never found as the free element in nature. Miners, stonecutters, and others engaged in work where siliceous dust is breathed into large quantities often develop a serious lung disease known as silicosis.American Elements: The Materials Science Company™ | Certified bulk & lab quantity manufacturer of metals, chemicals, nanoparticles & other advanced materials Elemental silicon transmits more than 95% of all wavelengths of infrared, from 1.3 to 6.y micro-m. Most acids, except hydrofluoric, do not affect it. Silicon is a relatively inert element, but it is attacked by halogens and dilute alkali. PropertiesĬrystalline silicon has a metallic luster and grayish color. Hydrolysis and condensation of various substituted chlorosilanes can be used to produce a very great number of polymeric products, or silicones, ranging from liquids to hard, glasslike solids with many useful properties. They may be prepared by hydrolyzing a silicon organic chloride, such as dimethyl silicon chloride. Silcones are important products of silicon. Silicon is an important ingredient in steel silicon carbide is one of the most important abrasives and has been used in lasers to produce coherent light of 4560 A. Silica is present in the ashes of plants and in the human skeleton. Diatoms in both fresh and salt water extract Silica from the water to build their cell walls. Silicon is important to plant and animal life. Hydrogenated amorphous silicon has shown promise in producing economical cells for converting solar energy into electricity. Hyperpure silicon can be doped with boron, gallium, phosphorus, or arsenic to produce silicon for use in transistors, solar cells, rectifiers, and other solid-state devices which are used extensively in the electronics and space-age industries. Silicon tetrachloride can be used as iridize glass. ![]() Glass can be made in a very great variety of shapes, and is used as containers, window glass, insulators, and thousands of other uses. Silica, as sand, is a principal ingredient of glass, one of the most inexpensive of materials with excellent mechanical, optical, thermal, and electrical properties. In the form of sand and clay it is used to make concrete and brick it is a useful refractory material for high-temperature work, and in the form of silicates it is used in making enamels, pottery, etc. Silicon is one of man's most useful elements. Hyperpure silicon can be prepared by the thermal decomposition of ultra-pure trichlorosilane in a hydrogen atmosphere, and by a vacuum float zone process. ![]() The Czochralski process is commonly used to produce single crystals of silicon used for solid-state or semiconductor devices. Amorphous silicon can be prepared as a brown powder, which can be easily melted or vaporized. Several other methods can be used for preparing the element. Silicon is prepared commercially by heating silica and carbon in an electric furnace, using carbon electrodes. are but a few of the numerous silicate minerals. Granite, hornblende, asbestos, feldspar, clay, mica, etc. Sand, quartz, rock crystal, amethyst, agate, flint, jasper, and opal are some of the forms in which the oxide appears. Silicon is not found free in nature, but occurs chiefly as the oxide and as silicates. Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, being exceeded only by oxygen. It is also a component of tektites, a natural glass of uncertain origin. Silicon is present in the sun and stars and is a principal component of a class of meteorites known as aerolites. Deville in 1854 first prepared crystalline silicon, the second allotropic form of the element. In 1824 Berzelius, generally credited with the discovery, prepared amorphous silicon by the same general method and purified the product by removing the fluosilicates by repeated washings. In 1800, Davy thought silica to be a compound and not an element but in 1811, Gay Lussac and Thenard probably prepared impure amorphous silicon by heating potassium with silicon tetrafluoride. Sand is one of the forms in which the oxide appears.Ĥ, 3, 2, 1 −1, −2, −3, −4 (an amphoteric oxide)įrom the Latin. (right) Silicon is not found free in nature, but occurs chiefly as the oxide and as silicates. ![]()
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