Silicon dioxide quartz

Silicon Dioxide (Quartz, Lechatelierite, Tri-dymite, Silica, Silicic Anhydride, Rock Crystal, Cristobalite, Sand). Si02, mw 60.08,... 

Production. Silicon is typically produced in a three-electrode, a-c submerged electric arc furnace by the carbothermic reduction of silicon dioxide (quartz) with carbonaceous reducing agents. The reductants consist of a mixture of coal (qv), charcoal, petroleum coke, and wood chips. Petroleum coke, if used, accounts for less than 10% of the total carbon requirements. Low ash bituminous coal, having a fixed carbon content of 55—70% and ash content of <4%, provides a majority of the required carbon. Typical carbon contribution is 65%. Charcoal, as a reductant, is highly reactive and varies in fixed carbon from 70—92%. Wood chips are added to the reductant mix to increase the raw material mix porosity, which improves the SiO (g) to solid carbon reaction. Silica is added to the furnace in the form of quartz, quartzite, or gravel. The key quartz requirements are friability and thermal stability. Depending on the desired silicon quality, the total oxide impurities in quartz may vary from 0.5—1%. 

In the different forms of silicon dioxide (quartz, tridymite, cristobalite, etc.), each silicon is surrounded by four oxygen atoms, each oxygen atom of a tetrahedral group Si04 being shared by two such groups. 

The synthesis of silicone starts vn th naturally occurring silicon dioxide (quartz, sand, or quartzite rock). Silicon dioxide is reacted with carbon at high temperature to yield elemental silicon. 

DL -tartaric acid mercury(II) oxide sodium potassium tartrate silicon dioxide (quartz) sodium chloride sucrose... 

Silicon is a prominent material of technology. The element is the basic material used in semiconductor devices for solid-state electronics. These devices require silicon of extreme purity. The impure element is converted to silicon tetrachloride, which is purified by distillation, after which the silicon tetrachloride is reduced to pure silicon. Silica is chemically known as silicon dioxide quartz is a common form of silica. It exhibits the piezoelectric ect, which is used to control radio, television, and clock frequencies. Silicates are formed by condensation reac-... 

Sample Problem F silicon dioxide (quartz) is usually quite unreactive but reacts readily with hydrogen fluoride according to the following equation. 

These interactions are therefore directional in nature. Other compounds that form covalent network crystals are silicon dioxide (quartz or cristobalite, Si02), graphite, elemental silicon (Si), boron nitride (BN), and black phosphorus. 

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