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bond, chemical
(Encyclopedia)bond, chemical: see chemical bond. ...lead, chemical element
(Encyclopedia)lead, metallic chemical element; symbol Pb [Lat. plumbum]; at. no. 82; at. wt. 207.2; m.p. 327.502℃; b.p. about 1,740℃; sp. gr. 11.35 at 20℃; valence +2 or +4. One of the oldest metals used by h...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...Henry's law
(Encyclopedia)Henry's law, chemical law stating that the amount of a gas that dissolves in a liquid is proportional to the partial pressure of the gas over the liquid, provided no chemical reaction takes place betw...flame
(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...catalyst
(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...surface chemistry
(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...Cs, chemical symbol
(Encyclopedia)Cs, symbol for the element cesium. ...CS, chemical compound
(Encyclopedia)CS, chemical compound (orthochlorobenzalmalonitrile) used in riot control and, by the military, as a harassing agent. The compound is dispersed as an aerosol or as a finely divided powder. Exposure to...copper, chemical element
(Encyclopedia)copper, metallic chemical element; symbol Cu [Lat. cuprum=copper]; at. no. 29; at. wt. 63.546; m.p. 1,083.4℃; b.p. 2,567℃; sp. gr. 8.96 at 20℃; valence +1 or +2. Copper and some of its alloys ha...Browse by Subject
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