(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 “…
(Encyclopedia) plutoniumplutoniumpl&oomacr;tōˈnēəm [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℃;…
(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…
(Encyclopedia) ethanolethanolĕthˈənōlˌ [key] or ethyl alcohol, CH3CH2OH, a colorless liquid with characteristic odor and taste; commonly called grain alcohol or simply alcohol.
Ethanol is used…
(Encyclopedia) zirconiumzirconiumzərkōˈnēəm [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.…
(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…
(Encyclopedia) Rossetti, Dante GabrielRossetti, Dante Gabrieldănˈtē gāˈbrēəl [key]Rossetti, Dante Gabriel rōsĕtˈē [key], 1828–82, English poet and painter; son of Gabriele Rossetti and brother of…
(Encyclopedia) benzenebenzenebĕnˈzēn, bĕnzēnˈ [key], colorless, flammable, toxic liquid with a pleasant aromatic odor. It boils at 80.1℃ and solidifies at 5.5℃. Benzene is a hydrocarbon, with formula…
(Encyclopedia) art conservation and restoration, the preservation of structurally sound works of art, the halting of processes that lead to the damage of works of art, and the repair of already…
