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Wayland

(Encyclopedia)Wayland, town (1990 pop. 11,874), Middlesex co., E Mass., W of Boston; settled c.1638, inc. 1835. Electronic and chemical research is carried on there. ...

reaction rate

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

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...

mineral, dietary

(Encyclopedia)mineral, dietary, any of a group of inorganic elements that are essential to humans and animals for normal body function. In nutrition, minerals are those elements for which the body's requirement is ...

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. ...

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. ...