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Simplified Chemistry

Amino acids

Organic compounds possessing one or more basic amino groups and one or more acidic carboxyl groups. Of the more than 80 amino acids which have been found in living organisms, about 20 serve as the building blocks for the proteins. All the amino acids of proteins, and most of the …

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Ascorbic Acid

Ascorbic acid A white, crystalline compound, also known as vitamin C. It is highly soluble in water, which is a stronger reducing agent than the hexose sugars, which it resembles chemically. Vitamin C deficiency in humans has been known for centuries as scurvy.The compound has the structural formula shown below. …

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Amid

Amide A derivative of a carboxylic acid with general formula RCONH2, where R is hydrogen or an alkyl or aryl radical. Amides are divided into subclasses, depending on the number of substituents on nitrogen. The simple, or primary, amides are considered to be derivatives formed by replacement of the carboxylic …

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Americium

A chemical element, symbol Am, atomic number 95. The isotope 241 Am is an alpha emitter with a half-life of 433 years. Other isotopes of americium range in mass from 232 to 247, but only the isotopes of mass 241 and 243 are important. The isotope 241Am is routinely separated …

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Alum

A colorless to white crystalline substance which occurs naturally as the mineral kalunite and is a constituent of the mineral alunite. Alum is produced as aluminum sulfate by treating bauxite with sulfuric acid to yield alum cake or by treating the bauxite with caustic soda to yield papermaker salum. Other …

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Alkyne

Alkyne One of a group of organic compounds containing a carbon-to-carbon triple-bond linkage (-C≡C-). They are termed acetylenes or alkynes. While exhibit­ing many of the characteristics of alkenes as regards unsaturation, the acetylenes have many unique properties. Since the bonding in alkyne molecules is linear. R-C≡C-R, cis-trans isomerism is not …

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Alkylation-petroleum

Alkylation (petroleum) In the petroleum industry, a chemical process in which an alkene (ethylene, propylene, and so forth) and a hydrocarbon, usually 2-methylpropane, are combined to produce a higher-molecular-weight and higher­carbon-number product. The product has a higher octane rating and is used to improve the quality of gasoline-range fuels. The …

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alkaloid

Alkaloid A cyclic organic compound that contains nitrogen in a negative oxidation state and is of limited distribution among living organisms. Over 10,000 alkaloids of many different structural types are known; and no other class of natural products possesses such an enormous variety of structures. Therefore, alkaloids are difficult to …

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Alkaline-earth metals

Usually calcium, strontium, and barium, the heav­iest members of group 2 of the periodic table (excepting radium). Other members of the group are beryllium, magnesium, and radium, sometimes included among the alkaline-earth metals. Beryllium resembles aluminum more than any other element, and magnesium behaves more like zinc and cadmium. The …

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Alkali

Any compound having highly basic properties, strong acrid taste, and ability to neutralize acids. Aqueous solutions of alkalies are high in hydroxyl ions, have a pH above 7, and turn litmus paper from red to blue. Caustic alkalies include sodium hydroxide (caustic soda), the sixth-largest-volume chemical produced in the United States, …

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