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.
Si element free#
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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