Simplified Chemistry

 

Biochemistry

Biochemistry The study of the substances and chemical processes which occur in living organisms. It includes the identification and quantitative determina­tion of the substances, studies of their structure, determining how they are synthe­sized and degraded in organisms, and elucidating their role in the operation of the organism.

Substances studied in biochemistry include carbohydrates (including simple sugars and large polysaccharides), proteins (such as enzymes), ribonucleic acid (RNA) and deoxyribonucleic…

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Biochemical engineering

Biochemical engineering The application of engineering principles to con­ceive, design, develop, operate, or use processes and products based on biological and biochemical phenomena. Biochemical engineering, a subset of chemical engineering, impacts a broad range of industries, including health care, agriculture, food, enzymes, chemicals, waste treatment, and energy. Historically, biochemical engineering has been distinguished from biomedical engineering by its emphasis on biochemistry and micro­biology and by the lack of…

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Beryllium

Beryllium A chemical element, Be, atomic number 4, with an atomic weight of 9.0122. Beryllium, a rare metal, is one of the lightest structural metals, having a density about one-third that of aluminum. Some of the important physical and chemical properties of beryllium are given in the table. Beryllium has a number of unusual and even unique properties

The largest volume uses of beryllium metal are in the…

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Berkelium

Berkelium Element number 97, symbol Bk, the eighth member of the actinide series of elements. In this series the Sf electron shell is being filled, just as the 4f shell is being filled in the lanthanide (rare-earth) elements. These two series of elements are very similar in their chemical properties, and berkelium, aside from small differences in ionic radius, is especially similar to its homolog terbium. Berkelium does…

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Benzoyl peroxide

Benzoyl peroxide A chemical compound, sometimes called dibenzoyl perox­ide, with the formula below. It is a colorless, crystalline solid, melting point 106-108°C (223-226°F), that is virtually insoluble in water but very soluble in most organic sol­vents. Benzoyl peroxide is an initiator, a type of material that decomposes at a controlled rate at moderate temperatures to give free radicals.

Benzoyl peroxide has a half-life (…

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Benzoic acid

Benzoic acid An organic acid, also known as benzene carboxylic acid, with the formula below. Melting point is 250.2°F (121.2°C), and the acid sublimes at 212°F (100°C). Benzoic acid is only slightly soluble in water but is soluble in most organic solvents, and reacts with bases to form the corresponding benzoate salts. Benzoic acid was first obtained by sublimation from gum benzoin. It occurs both free and combined…

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Benzene

Benzene A colorless, liquid, inflammable, aromatic hydrocarbon of chemical for­mula C6H6 which boils at 80.l°C (176.2°F) and freezes at 5.4-5.5°C (41.7-41.9°F). In the older American and British technical literature benzene is designated by the Ger­man name benzol. In current usage the term benzol is commonly reserved for the less pure grades of benzene.

Benzene is used as a solvent and…

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Base

Base (chemistry) In the Brensted- Lowry classification, any chemical species, ionic or molecular, capable of accepting or receiving a proton {hydrogen ion) from another substance. The other substance acts as an acid in giving up the proton. A substance may act as a base, then, only in the presence of an acid. The greater the ten­dency to accept a proton, the stronger the base. The hydroxyl ion acts…

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Barium

Barium A chemical element, Ba, with atomic number 56 and atomic weight of 137.34. Barium is eighteenth in abundance in the Earth’s crust, where it is found to the extent of 0.04%, making it intermediate in amount between calcium and strontium, the other alkaline-earth metals. Barium compounds are obtained from the mining and conversion of two barium minerals. Barite, barium sulfate, is the principal ore and contains 65.79%…

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Balance

Balance An instrument used for the precise measurement of small weights or masses in amounts ranging from micrograms up to a few kilograms.

Balances are differentiated according to design, weighing principle, and metrological criteria . For a given weighing task, a balance is selected primarily for its maximum weighing load (Max) and for the finest graduation or division (d) of its weight-reading device (scale…

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