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ratchet and pawl
(Encyclopedia)ratchet and pawl, mechanical device that permits motion in one direction only. The ratchet is usually a wheel with slanting teeth. The pawl is a lever tangential to the wheel with one end resting on t...oxidation and reduction
(Encyclopedia)oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation was used to re...acids and bases
(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...rock and roll
(Encyclopedia)rock and roll: see rock music.periodic table
(Encyclopedia) CE5 periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arrange...oxygen
(Encyclopedia)oxygen, gaseous chemical element; symbol O; at. no. 8; interval in which at. wt. ranges 15.99903–15.99977; m.p. −218.4℃; b.p. −182.962℃; density 1.429 grams per liter at STP; valence −2. T...cone, in botany
(Encyclopedia)cone or strobilus strŏbˈələs [key], in botany, reproductive organ of the gymnosperms (the conifers, cycads, and ginkgoes). Like the flower in the angiosperms (flowering plants), the cone is actual...cone, in mathematics
(Encyclopedia) CE5 Cone cone or conical surface, in mathematics, surface generated by a moving line (the generator) that passes through a given fixed point (the vertex) and continually intersects a given fixed c...conglomerate, in business
(Encyclopedia)conglomerate, corporation whose asset growth, often very rapid, comes largely through the acquisition of, or merger with, other firms whose products are largely unrelated to each other or to that of t...conglomerate, in geology
(Encyclopedia)conglomerate, in geology, sedimentary rock composed largely of pebbles or other rounded particles whose diameter is larger than 2 mm (.08 in.). Essentially a cemented gravel, conglomerates are formed ...Browse by Subject
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