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weight lifting

(Encyclopedia)weight lifting, international sport, also a training technique for athletes in other sports. From the earliest times men have lifted weights as a test of strength. Long popular as a competitive sport ...

law of simple multiple proportions

(Encyclopedia)law of simple multiple proportions, in chemistry, the statement that when two or more elements form more than one compound, the ratio of the weights of one element that combine with a given weight of ...

molecular orbital theory

(Encyclopedia)molecular orbital theory, detailed explanation of how electrons are distributed in stable molecules. In the simpler valence theory of the chemical bond, each atom in a molecule is assumed to retain it...

hydrocarbon

(Encyclopedia)hydrocarbon hīˌdrōkärˈbən [key], any organic compound composed solely of the elements hydrogen and carbon. The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their ...

Avogadro, Amedeo, conte di Quaregna

(Encyclopedia)Avogadro, Amedeo, conte di Quaregna ämādāˈō kônˈtā dē kwärāˈnyä ävōgäˈdrō [key], 1776–1856, Italian physicist, b. Turin. He became professor of physics at the Univ. of Turin in 182...

lipoprotein

(Encyclopedia)lipoprotein lĭpˌəprōˈtēn [key], any organic compound that is composed of both protein and the various fatty substances classed as lipids, including fatty acids and steroids such as cholesterol. ...

aldehyde

(Encyclopedia)CE5 Aldehydes aldehyde ălˈdəhīd [key] [alcohol + New Lat. dehydrogenatus=dehydrogenated], any of a class of organic compounds that contain the carbonyl group, >C=-->O, and in which t...

paraffin

(Encyclopedia)paraffin, white, more-or-less translucent, odorless, tasteless, waxy solid. It melts between 47℃ and 65℃ and is insoluble in water but soluble in ether, benzene, and certain esters. Paraffin is un...

surface chemistry

(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...

Henderson, Richard, Scottish molecular biologist

(Encyclopedia)Henderson, Richard, 1945–, Scottish molecular biologist, Ph.D. Cambridge, 1969. Henderson has been a researcher at the Laboratory of Molecular Biology in Cambridge since 1973. In 2017 he was awarded...