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ammonia
(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...xylene
(Encyclopedia)xylene dīˌmĕthəlbĕnˈzēn [key], C6H4(CH3)2, colorless, oily, liquid aromatic hydrocarbon, used extensively as a solvent, obtained from coal tar, wood tar, and sometimes from petroleum. It is a m...glycerol
(Encyclopedia)glycerol, glycerin, glycerine, or 1,2,3-propanetriol prōˈpāntrīˌŏl [key], CH2OHCHOHCH2OH, colorless, odorless, sweet-tasting, syrupy liquid. Glycerol is a trihydric alcohol. It melts at 17.8...adsorption
(Encyclopedia)adsorption, adhesion of the molecules of liquids, gases, and dissolved substances to the surfaces of solids, as opposed to absorption, in which the molecules actually enter the absorbing medium (see a...salt, chemical compound
(Encyclopedia)salt, chemical compound (other than water) formed by a chemical reaction between an acid and a base (see acids and bases). Salts are also prepared by methods other than neutralization. A metal can c...ester
(Encyclopedia)CE5 Esters ester, any one of a group of organic compounds with general formula RCO2R′ (where R and R′ are alkyl groups or aryl groups) that are formed by the reaction between an alcohol and an...glycol
(Encyclopedia)glycol glīˈkōl [key], dihydric alcohol in which the two hydroxyl groups are bonded to different carbon atoms; the general formula for a glycol is (CH2)n(OH)2. The most important glycol is the simpl...mixture
(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...rare-earth metals
(Encyclopedia)rare-earth metals, in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, whi...ultrasonics
(Encyclopedia)ultrasonics, study and application of the energy of sound waves vibrating at frequencies greater than 20,000 cycles per second, i.e., beyond the range of human hearing. The application of sound energy...Browse by Subject
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