348 results found
sulfur dioxide(Encyclopedia)sulfur dioxide, chemical compound, SO2, a colorless gas with a pungent, suffocating odor. It is readily soluble in cold water, sparingly soluble in hot water, and soluble in alcohol, acetic acid, and ...
acid anhydride(Encyclopedia)acid anhydride nh´drd, –drd [key], chemical compound that reacts with water to form an acid (see acids and bases). Anhydrides of inorganic acids are usually oxides of nonmetallic elements. ...
cinnabar(Encyclopedia)cinnabar sn´bär [key], mineral, the sulfide of mercury, HgS. Deep red in color, it is used as a pigment (see vermilion), but principally it is a source of the metal mercury. It is mined in Spain...
sulfuric acid(Encyclopedia)sulfuric acid, chemical compound, H2SO4, colorless, odorless, extremely corrosive, oily liquid. It is sometimes called oil of vitriol. Concentrated Sulfuric Acid When heated, the pure 100% acid loses ...
oxide(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...
sodium thiosulfate(Encyclopedia)sodium thiosulfate, Na2S2O3, colorless crystalline compound that is more familiar as the pentahydrate, Na2S2O3·5H2O, an efflorescent, monoclinic crystalline substance also called sodium hyposulfite o...
sulfur(Encyclopedia)sulfur or sulphursl´fr [key], nonmetallic chemical element; symbol S; at. no. 16; interval in which at. wt. ranges 32.059–32.076; m.p. 112.8°C (rhombic), 119.0°C (monoclinic), about 120°C (a...
sulfide(Encyclopedia)sulfide, chemical compound containing sulfur and one other element or sulfur and a radical. Sulfides may be salts or esters of hydrogen sulfide, H2S, or may be formed directly, e.g., by heating a meta...
acid rain(Encyclopedia)acid rain or acid deposition, form of precipitation (rain, snow, sleet, or hail) containing high levels of sulfuric or nitric acids (pH below 5.5–5.6). Produced when sulfur dioxide and various nitro...
Io(Encyclopedia)Io ´ [key], in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. Io is subject to Jupiter's enormous tidal forces and is, as a result, the most volcanically active body in ...
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