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Tennant, Smithson

(Encyclopedia)Tennant, Smithson, 1761–1815, English chemist. In 1796 he proved, by burning a diamond, that the diamond consists solely of carbon. In 1804 he announced his discovery of osmium and iridium. ...

element

(Encyclopedia)CE5 element, in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compound can be decomposed into its constituent elements by means o...

butadiene

(Encyclopedia)butadiene byo͞otˌədīˈēn [key], colorless, gaseous hydrocarbon. There are two structural isomers of butadiene; they differ in the location of the two carbon-carbon double bonds in the butadiene m...

butane

(Encyclopedia)butane byo͞oˈtān [key], C4H10, gaseous alkane, a hydrocarbon that is obtained from natural gas or by refining petroleum. It can be liquefied at room temperature by compression. There are two struct...

aromatic compound

(Encyclopedia)aromatic compound, any of a large class of compounds that includes benzene and compounds that resemble benzene in certain of their chemical properties. Originally applied to a small class of pleasant-...

intoxication

(Encyclopedia)intoxication, condition of body tissue affected by a poisonous substance. Poisonous materials, or toxins, are to be found in heavy metals such as lead and mercury, in drugs, in chemicals such as alcoh...

heat of combustion

(Encyclopedia)heat of combustion, heat released during combustion. In particular, it is the amount of heat released when a given amount (usually 1 mole) of a combustible pure substance is burned to form incombustib...

Novoselov, Sir Konstantin Sergeevich

(Encyclopedia)Novoselov, Sir Konstantin Sergeevich, 1974–, Russian-British physicist, Ph.D. Univ. of Nijmegen, Netherlands, 2004. He has been a research associate at the Univ. of Manchester, England, since 2001. ...

autotroph

(Encyclopedia)autotroph ôtˈətrōfˌ [key], in biology, an organism capable of synthesizing its own organic substances from inorganic compounds. Autotrophs produce their own sugars, lipids, and amino acids using ...

coal

(Encyclopedia)coal, fuel substance of plant origin, largely or almost entirely composed of carbon with varying amounts of mineral matter. Coal is found in beds or seams interstratified with shales, clays, sands...