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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...

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...

Heck, Richard Fred

(Encyclopedia)Heck, Richard Fred, 1931–2015, American chemist, b. Springfield, Mass., Ph.D. Univ. of California, Los Angeles, 1954. Heck was a researcher at the Hercules Corporation in Wilmington, Del., from 1957...

Pennsylvania, University of

(Encyclopedia)Pennsylvania, University of, in Philadelphia; private with some state support; coeducational. It dates to 1740 and plans for a charity school, and the first predecessor opened in 1751 as an academy, l...

Betzig, Robert Eric

(Encyclopedia)Betzig, Robert Eric, 1960–, American physicist, b. Ann Arbor, Mich., Ph.D. Cornell, 1988. Betzig worked at AT&T Bell Laboratories from 1988 to 1996, when he become vice president of research and...

nitrate

(Encyclopedia)nitrate, chemical compound containing the nitrate (NO3) radical. Nitrates are salts or esters of nitric acid, HNO3, formed by replacing the hydrogen with a metal (e.g., sodium or potassium) or a radic...

Le Châtelier's principle

(Encyclopedia)Le Châtelier's principle, chemical principle that states that if a system in equilibrium is disturbed by changes in determining factors, such as temperature, pressure, and concentration of components...

vacuum

(Encyclopedia)vacuum, theoretically, space without matter in it. A perfect vacuum has never been obtained; the best human-generated vacuums contain less than 100,000 gas molecules per cc, compared to about 30 billi...

Noyori, Ryoji

(Encyclopedia)Noyori, Ryoji, 1938–, Japanese chemist, D.Eng. Kyoto Univ., 1967. Noyori was an instructor at Kyoto Univ. from 1963 to 1968. He then joined the faculty at Nagoya Univ., where he is a professor and d...

Mendeleev, Dmitri Ivanovich

(Encyclopedia)Mendeleev, Dmitri Ivanovich mĕndəlāˈəf, Rus. dəmēˈtrē ēväˈnəvĭch myĭndyĭlyāˈəf [key], 1834–1907, Russian chemist. He is famous for his formulation (1869) of the periodic law and t...