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Sonora

(Encyclopedia)Sonora sōnōˈrä [key], state (1990 pop. 1,823,606), 70,484 sq mi (182,554 sq km), NW Mexico, on the Gulf of California, S of Arizona. Hermosillo is the capital. Sonora is mostly mountainous, with v...

wire

(Encyclopedia)wire, metal filament, strand, or solid rod usually having a round cross section. Metals and alloys used for wiremaking are chosen for high tensile strength and ductility or for their electrical conduc...

calcium

(Encyclopedia)calcium kălˈsēəm [key] [Lat.,=lime], metallic chemical element; symbol Ca; at. no. 20; at. wt. 40.078; m.p. about 839℃; b.p. 1,484℃; sp. gr. 1.55 at 20℃; valence +2. Calcium is a malleable, ...

phosphorus

(Encyclopedia)phosphorus fŏsˈfərəs [key] [Gr.,=light-bearing], nonmetallic chemical element; symbol P; at. no. 15; at. wt. 30.97376; m.p. 44.1℃; b.p. about 280℃; sp. gr. 1.82 at 20℃; valence −3, +3, or ...

catalyst

(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...

meteor

(Encyclopedia)meteor, appearance of a small particle flying through space that interacts with the earth's upper atmosphere. While still outside the atmosphere, the particle is known as a meteoroid. Countless meteor...

Toltec

(Encyclopedia)Toltec tŏlˈtĕk [key], ancient civilization of Mexico. The name in Nahuatl means “master builders.” The Toltec formed a warrior aristocracy that gained ascendancy in the Valley of Mexico c.a.d. ...

coin

(Encyclopedia)coin, piece of metal, usually a disk of gold, silver, nickel, bronze, copper, aluminum, or a combination of such metals, stamped by authority of a government as a guarantee of its real or exchange val...

cold fusion

(Encyclopedia)cold fusion or low-temperature fusion, nuclear fusion of deuterium, an isotope of hydrogen, at or relatively near room temperature. Fusion, the reaction involved in the release of the destructive ener...

Greenville

(Encyclopedia)Greenville. 1 City (2020 pop. 29,670, seat of Washington co., W Miss., on Lake Ferguson, a deepwater harbor adjoining the Mississippi River; inc. ...