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carbide

(Encyclopedia)carbide, any one of a group of compounds that contain carbon and one other element that is either a metal, boron, or silicon. Generally, a carbide is prepared by heating a metal, metal oxide, or metal...

catchment area

(Encyclopedia)catchment area or drainage basin, area drained by a stream or other body of water. The limits of a given catchment area are the heights of land—often called drainage divides, or watersheds—separat...

hydrogen peroxide

(Encyclopedia)hydrogen peroxide, chemical compound, H2O2, a colorless, syrupy liquid that is a strong oxidizing agent and, in water solution, a weak acid. It is miscible with cold water and is soluble in alcohol an...

borax

(Encyclopedia)borax or sodium tetraborate decahydrate sōˈdēəm tĕˌtrəbôrˈāt dĕkˌəhīˈdrāt [key], chemical compound, Na2B4O7·10H2O; sp. gr. 1.73; slightly soluble in cold water; very soluble in hot wa...

stalactite and stalagmite

(Encyclopedia)stalactite stəlăgˈmīt [key], mineral forms often found in caves; sometimes collectively called dripstone. A stalactite is an icicle-shaped mass of calcite attached to the roof of a limestone caver...

Philadelphia, city, United States

(Encyclopedia)Philadelphia, city (2020 pop. 1,603,797), coextensive with Philadelphia co., SE Pa., on the Delaware River c.100 mi (160 km) upstream at the influx of t...

compound

(Encyclopedia)compound, in chemistry, a substance composed of atoms of two or more elements in chemical combination, occurring in a fixed, definite proportion and arranged in a fixed, definite structure. A compound...

Ames

(Encyclopedia)Ames, city (2020 pop. 66,427), Story co., central Iowa, on the Skunk River; inc. 1870. Its chief manufactures are electronic, water-analysis, and water-treatment equipment; motor vehicles;...

barium

(Encyclopedia)barium bârˈēəm [key] [Gr.,=heavy], metallic chemical element; symbol Ba; at. no. 56; at. wt. 137.327; m.p. 725℃; b.p. 1,640℃; sp. gr. 3.5 at 20℃; valence +2. Barium is a soft, silver-white, ...

diving, springboard and platform

(Encyclopedia)diving, springboard and platform, sport of entering the water from a raised position, often while executing tumbles, twists, and other acrobatic maneuvers. In most dives the upper part of the body ent...