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reaction rate

(Encyclopedia)reaction rate: see chemical reaction. ...

Tm

(Encyclopedia)Tm, chemical symbol for the element thulium. ...

resonance, in chemistry

(Encyclopedia)resonance, in chemistry: see chemical bond. ...

photoelectric effect

(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...

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...

stannic

(Encyclopedia)stannic: a chemical compound containing tin in the +4 valence state. ...

stannous

(Encyclopedia)stannous: a chemical compound containing tin in the +2 valence state. ...

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. ...

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...