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Home >> Chemistry Dictionary >> Bio Genic Amines Birkland Eyde Process
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BHT. 2,6-Di-tert-butyl-4-methylphenol.
Bi. Bismuh.
Biacetyl. See diacetyl.
Bicarbonates. Hydrogen carbonates.
Bidentate. A legand that coordinate through two bonds from different parts of the molecule or anion, e.g., carbonate, oxalate and ethylenediamine (NH2CH2CH2NH2).
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Bimetallic couple. Any pair of different metals which, when immersed in a solution of an electrolyte, form an electrochemical cell, and produce a galvanic corrosion.
Bimolecular reaction. A chemical reaction in which two molecules or other species react together, e.g., H2 + I2 → 2HI.
Binary compound. A compound containing two elements, e.g. NiAs
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Binding energy. The energy needed to pull the nucleons of the nucleus apart or the energy needed to pull the nucleons of the nucleus apart or the energy released by the individual nucleons. It may be calculated from the difference between the sum of the masses of the constituent nucleons and the mass of the corresponding nucleons and For CI, this mass difference is 0.3204 and, therefore, 0.3204 × 931Me v/u = 298 MeV
The amount of the binding energy of a given nucleus tells the stability of that nucleus toward radioactive decay.
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Bio assay. Quantitative and sometimes qualitative analysis by determining effect on a test organism. Used particularly for substances having a large physiological effect.
Bio genic amines. An important group of naturally occurring amines derived by enzymic decarboxylation of the natural amino acids.
Biose. A carbohydrate with two carbon atoms. The only biose is glycolic aldehyde, CHO.CH2OH.
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Biosynthesis. A term describing the processes by which living organisms build up the compounds and structures required for their further growth and reproduction. Ultimately the build-up is from CO2H2O, light energy and inorganic compounds; however, the complete sequence only takes place in photosynthetic organisms. The term biogenesis is not quite synonymous, as it may also be used to refer to non-synthetic biological transformation.
Biotin. One of the vitamin-B factors. Biotin is present in yeast, egg yolk, liver and other tissues.
Birland-Eyde Process. An atmospheric nitrogen and oxygen can be made to combine under the influence of an electric arc (temperature 3000-3500˚C) to give nitric oxide.
N2 + O2 → 2NO ∆H = + 43 kcal.
The nitric oxide is, oxidised to nitrogen dioxide which is then absorbed water to give nitric acid.
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Bisabolene. C15H24. One of the most widely distributed sesquiter-penes.
Bismarck brown, Basic brown. A Basic azodyestuff, dyes wool used for cotton with tannin as mordant. Also used as hair dye.
Bismuth. Bi. At.no. 83, at.wt. 208.9808, m.p 271.3˚C, b.p. 1560˚C, d 9.8. A Group Velement occurring native in sulphide ores, and as Bi2S3 (bismuth glance) and in Cu, Sn and Pb ores. The ores are roasted to Bi2O3 and reduced to the metal with H2 or C. The metal is brittle, reddish-white in colour with the As and Sb structure (double layers with 3 near neighbours and 3 far). Bi burns in air to Bi2 O3 and is only slowly attacked by acids. It is used extensively in low melting alloys and for making casting. BiOCI is used in cosmetics and some Bi compounds are used medically and Bi is used in alloys used in electronics.
Bismuth alloys. Alloys of bismuth with Pb, Sn and Cd of low m.p. Used for fire protective devices, fuses, solders, etc.
Bismuthates (V). Formed from e.g. Na2O3 and Bi2O3 (impure NaBiO3). Never formed pure, they are very strong oxidizing agents (e.g. Mn2 + to MnO-4 in acid solution).
Bismuth carbonates. Bi2O2CO3 -  H2 O(Bi3+ plus soluble carbonate) is precipitated from solution. Loses H2O at 100˚C. Used for the relief of indigestion.
Bismuth hydride. BiH3 A very unstable toxic gas (Mg-Bi plus acid).
Bismuth oxides. Bi2O3 (Bi3+ plus alkali to give Bi(OH)3 then dehydration) is the only definite oxide. It is yellow and dissolves in acids to salts (e.g. nitrate, sulphate). Used in porcelain glazes and stained glass. Bi2O5 (oxidizing agents on Bi2O3) is unstable and has never been obtained pure.
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