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Tm
(Encyclopedia)Tm, chemical symbol for the element thulium. ...resonance, in chemistry
(Encyclopedia)resonance, in chemistry: see chemical bond. ...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...activation energy
(Encyclopedia)CE5 Energy profile of an exothermic reaction: Although the total energy of the products is less than that of the reactants, the activation energy must be added to weaken or break existing bonds bef...designer drug
(Encyclopedia)designer drug, chemical substance synthesized in a laboratory that is intended to have effects similar to those of a drug that is a controlled substance, such as methamphetamine, marijuana, LSD, or an...CN (tear gas)
(Encyclopedia)CN, ordinary tear gas. The chemical name for CN is chloroacetophenone. ...Silurian period
(Encyclopedia)Silurian period sĭlo͝orˈēən, sī– [key] [from the Silures, ancient tribe of S Wales, where the period was first studied; named by the British geologist R. I. Murchison], third period of the Pal...Monroeville
(Encyclopedia)Monroeville, borough (1990 pop. 29,169), Allegheny co., SW Pa., a suburb of Pittsburgh; settled 1810, inc. 1952. It is primarily residential, with a major shopping mall. Monroeville has chemical and n...Crookes, Sir William
(Encyclopedia)Crookes, Sir William, 1832–1919, English chemist and physicist. After serving at the Radcliffe Observatory, Oxford, and teaching chemistry at Chester Training College, he retired to work in his own ...Pople, Sir John Anthony
(Encyclopedia)Pople, Sir John Anthony pōpˈəl [key], 1925–2004, British computational chemist. Trained as a mathematician at Cambridge (B.A. 1946, Ph.D. 1951), he worked at Cambridge (1951–58) and England's N...Browse by Subject
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