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aryl group

(Encyclopedia)aryl group ârˈĭl [key], in chemistry, group of atoms derived from benzene or from a benzene derivative by removing one hydrogen that is bonded to the benzene ring (see radical). The simplest aryl g...

alkyl group

(Encyclopedia)alkyl group ălˈkĭl [key], in chemistry, group of carbon and hydrogen atoms derived from an alkane molecule by removing one hydrogen atom (see radical). The name of the alkyl group is derived from t...

functional group

(Encyclopedia)CE5 functional group, in organic chemistry, group of atoms within a molecule that is responsible for certain properties of the molecule and reactions in which it takes part. Organic compounds are f...

cyano group

(Encyclopedia)cyano group sīˈənō, sī-ănˈō [key], in chemistry, functional group that consists of a carbon atom joined to a nitrogen atom by a triple bond; it can be joined to an atom or another group by a s...

oxy group

(Encyclopedia)oxy group ŏkˈsē [key], in chemistry, functional group that consists of an oxygen atom joined by single bonds to two separate alkyl groups or aryl groups. It is the functional group of ethers. ...

carbonyl group

(Encyclopedia)carbonyl group kärˈbənĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a double bond to a carbon atom. The carbon atom is joined to the remainder of the molecule ...

Bloomsbury group

(Encyclopedia)Bloomsbury group, name given to the literary group that made the Bloomsbury area of London the center of its activities from 1904 to World War II. It included Lytton Strachey, Virginia Woolf, Leonard ...

Local Group

(Encyclopedia)Local Group, in astronomy, loose cluster of at least 40 nearby galaxies, including our own Milky Way galaxy, the Andromeda Galaxy, and the Magellanic Clouds. The Local Group is spread over an ellipsoi...

prosthetic group

(Encyclopedia)prosthetic group, non-amino acid portions of certain protein molecules. The key part of the prosthetic group may be either organic (such as a vitamin) or inorganic (such as a metal) and is usually req...

Seven Weeks War

(Encyclopedia)Seven Weeks War: see Austro-Prussian War. ...