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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...boiling point
(Encyclopedia)boiling point, temperature at which a substance changes its state from liquid to gas. A stricter definition of boiling point is the temperature at which the liquid and vapor (gas) phases of a substanc...complex ion
(Encyclopedia)complex ion, charged molecular aggregate (see ion), consisting of a metallic atom or ion to which is attached one or more electron-donating molecules. In some complex ions, such as sulfate, SO4−2, t...gasoline
(Encyclopedia)gasoline or petrol, light, volatile mixture of hydrocarbons for use in the internal-combustion engine and as an organic solvent, obtained primarily by fractional distillation and “cracking” of pet...plutonium
(Encyclopedia)plutonium plo͞otōˈnēəm [key], radioactive chemical element; symbol Pu; at. no. 94; mass no. of most stable isotope 244; m.p. 641℃; b.p. 3,232℃; sp. gr. 19.84 at 20℃; valence +3, +4, +5, or ...diffusion
(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...ethanol
(Encyclopedia)ethanol ĕthˈənōlˌ [key] or ethyl alcohol, CH3CH2OH, a colorless liquid with characteristic odor and taste; commonly called grain alcohol or simply alcohol. Ethanol is used extensively as a solv...zirconium
(Encyclopedia)zirconium zərkōˈnēəm [key], metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.224; m.p. about 1,852℃; b.p. 4,377℃; sp. gr. 6.5 at 20℃; valence +2, +3, or +4. Zirconium is a very ...molecular weight
(Encyclopedia)molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the ato...Rossetti, Dante Gabriel
(Encyclopedia)Rossetti, Dante Gabriel rōsĕtˈē [key], 1828–82, English poet and painter; son of Gabriele Rossetti and brother of Christina Rossetti. He attended the Royal Academy and studied painting briefly ...Browse by Subject
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