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ketone

(Encyclopedia)CE5 Ketones ketone kēˈtōn [key], any of a class of organic compounds that contain the carbonyl group, C=O, and in which the carbonyl group is bonded only to carbon atoms. The general formula fo...

colligative properties

(Encyclopedia)colligative properties, properties of a solution that depend on the number of solute particles present but not on the chemical properties of the solute. Colligative properties of a solution include fr...

cellulose

(Encyclopedia)cellulose, chief constituent of the cell walls of plants. Chemically, it is a carbohydrate that is a high molecular weight polysaccharide. Raw cotton is composed of 91% pure cellulose; other important...

calorie

(Encyclopedia)calorie, abbr. cal, unit of heat energy in the metric system. The measurement of heat is called calorimetry. The calorie, or gram calorie, is the quantity of heat required to raise the temperature of ...

tetracycline

(Encyclopedia)tetracycline tĕˌtrəsīˈklēn [key], any of a group of antibiotics produced by bacteria of the genus Streptomyces. Effective against a wide range of Gram positive and Gram negative bacteria, tetrac...

lincomycin

(Encyclopedia)lincomycin lĭngˌkōmīˈsĭn [key], antibiotic isolated from bacteria of the genus Streptomyces. Similar in activity to erythromycin, it is effective against most gram-positive organisms including s...

ampicillin

(Encyclopedia)ampicillin ămˌpĭsĭlˈĭn [key], a penicillin-type antibiotic that is effective against both gram-negative microorganisms and gram-positive microorganisms such as Escherichia coli. It is often used...

bacitracin

(Encyclopedia)bacitracin băsˌĭtrāˈsĭn [key], antibiotic produced by a strain of the bacterial species Bacillus subtilis. It is widely used for topical therapy such as for skin and eye infections; it is effect...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

silicone

(Encyclopedia)silicone, polymer in which atoms of silicon and oxygen alternate in a chain; various organic radicals, such as the methyl group, CH3, are bound to the silicon atoms. Silicones, which are unusually sta...