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silver

(Encyclopedia)silver, metallic chemical element; symbol Ag [Lat. argentum]; at. no. 47; at. wt. 107.8682; m.p. 961.93℃; b.p. 2,212℃; sp. gr. 10.5 at 20℃; valence +1 or +2. Pure silver is nearly white, lustrou...

photosynthesis

(Encyclopedia)photosynthesis fōˌtōsĭnˈthəsĭs [key], process in which green plants, algae, and cyanobacteria utilize the energy of sunlight to manufacture carbohydrates from carbon dioxide and water in the pr...

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...

Al Qaeda

(Encyclopedia)Al Qaeda or Al Qaida äl kīˈĕdə, käˈĭdä [key] [Arab.,=the base], Sunni Islamic terrorist organization with the stated goals of uniting all Muslims and establishing a transnational, strict-fund...

mulberry

(Encyclopedia)CE5 Red mulberry, Morus rubra mulberry, common name for the Moraceae, a family of deciduous or evergreen trees and shrubs, often climbing, mostly of pantropical distribution, and characterized by ...

nickel

(Encyclopedia)nickel, metallic chemical element; symbol Ni; at. no. 28; at. wt. 58.6934; m.p. about 1,453℃; b.p. about 2,732℃; sp. gr. 8.902 at 25℃; valence 0, +1, +2, +3, or +4. Nickel is a hard, malleable, ...

valence, in chemistry

(Encyclopedia)valence, combining capacity of an atom expressed as the number of single bonds the atom can form or the number of electrons an element gives up or accepts when reacting to form a compound. Atoms are c...

sodium chloride

(Encyclopedia)sodium chloride, NaCl, common salt. Salt is important in many ways. It is an essential part of the diet of both humans and animals and is a part of most animal fluids, such as blood, sweat, and te...

photographic processing

(Encyclopedia)photographic processing, set of procedures by which the latent, or invisible, image produced when a photographic film is exposed to light is made into a permanent visible image. The negative may b...

canoe

(Encyclopedia)canoe kəno͞oˈ [key], long, narrow watercraft with sharp ends originally used by most peoples. It is usually propelled by means of paddles, although sails and, more recently, outboard motors are als...