الرئيسية » Simplified Chemistry (صفحه 2)

Simplified Chemistry

Birkeland–Eyde process

An industrial process for fixing nitrogen (as nitrogen monoxide) by passing air through an electric arc. It is one of the first processes to take place while manufacturing nitrogen based fertilizers. It was developed by Norwegian physicist and chemist Kristian Olaf Bernhard Birkeland (1867–1917) and the Norwegian engineer and industrialist …

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Bohrium

A chemical element, symbol Bh, atomic number 107. Bohrium was synthesized and identified in 1981 by using the Universal Linear Accelerator (UNILAC) of the Gesellschaft fur Schwerionenforschung (GSI) at Darmstadt, West Germany, by a team led by P. Armbruster and G. Muzenberq. The reaction used to produce the element was …

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Important bismuth compounds

Bismuth(III) carbonate dioxide : (bismuthyl carbonate; Bi2O2CO3) A white solid prepared by mixing solutions of bismuth nitrate and ammonium carbonate. It contains the (BiO)+ ion. Bismuth(III) chloride (bismuth trichloride; BiCl3) A white deliquescent solid. It can be prepared by direct combination of bismuth and chlorine. Bismuth(III) chloride dissolves in excess …

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important beryllium compounds

Beryllium carbonate (BeCO₃) , molecular weight: 69.021 g/mol , melting point: 54 °C  . It is An unstable solid prepared by prolonged treatment of a suspension of beryllium hydroxide with carbon dioxide. The resulting solution is evaporated and filtered in an atmosphere of carbon dioxide. This compound is toxic, Irritant and …

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Beckmann thermometer

A type of thermometer designed to measure differences in temperature rather than scale degrees. Beckmann thermometers have a larger bulb than common thermometers and a stem with a small internal diameter, so that a range of 5°C covers about 30 centimeters in the stem. The mercury bulb is connected to …

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Batch process

A manufacturing process in which the reactants are fed into the process in fixed quantities (batches), rather than in a continuous flow. At any particular instant all the material, from its preparation to the final product, has reached a definite stage in the process. Baking a cake is an example …

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Bessemer process

A process for making steel from pig iron. A vertical cylindrical steel vessel (converter) is used, lined with a refractory material. Air is blown through the molten iron and carbon is oxidized and thus removed from the iron. Other impurities – silicon, sulfur, and phosphorus – are also oxidized. Irons containing large amounts of phosphorus are treated in a …

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important barium compound

Barium carbonate (BaCO₃), molecular weight: 197.34 g/mol  , density: 4.286 g/cm3 , melting point: 811 °C .  It is a white insoluble salt that occurs naturally as the mineral witherite. Barium carbonate can be readily precipitated by adding an alkali carbonate to a barium salt solution. On heating it decomposes reversibly with the formation of the oxide and …

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Banana bond

1. In strained-ring compounds the angles assumed on the basis of hybridization are often not equal to the angles obtained by joining the atomic centers. In these cases it is sometimes assumed that the bonding orbital is bent or banana-like in shape. Cyclopropane is an example, in which geometric considerations …

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Auger effect

An effect in which an excited ion decays by emission of an electron (rather than a photon). For example, if a substance is bombarded by high-energy electrons or gamma rays, an electron from an inner shell may be ejected. The result is a positive ion in an excited state. This …

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