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science

(Encyclopedia)science [Lat. scientia=knowledge]. For many the term science refers to the organized body of knowledge concerning the physical world, both animate and inanimate, but a proper definition would also hav...

ion, in chemistry

(Encyclopedia)ion, atom or group of atoms having a net electric charge. Ionization has many applications. Vapor lamps and fluorescent lamps take advantage of the light given off when positive ions recombine with ...

fluorine

(Encyclopedia)fluorine flo͞oˈərēn, –rĭn [key], gaseous chemical element; symbol F; at. no. 9; at. wt. 18.9984; m.p. −219.6℃; b.p. −188.14℃; density 1.696 grams per liter at STP; valence −1. Fluorin...

food preservation

(Encyclopedia)food preservation, methods of preparing food so that it can be stored for future use. Because most foods remain edible for only a brief period of time, people since the earliest ages have experimented...

electric circuit

(Encyclopedia)CE5 A. Series circuit: Current is the same through each resistance; voltage divides in direct proportion to each resistance. B. Parallel circuit: Voltage drop is the same over each resistance; curr...

earth, in geology and astronomy

(Encyclopedia)CE5 A. Cross section of the earth, showing its shells B. Detailed cross section of the crust and upper mantle: The lithosphere consists of the hard rock in the crust and upper mantle, lying above t...

Miami, cities, United States

(Encyclopedia)Miami mīămˈē, –ə [key]. 1 City (1990 pop. 358,548), seat of Dade co., SE Fla., on Biscayne Bay at the mouth of the Miami River; inc. 1896. The region of Greater Miami encompasses all of Dade co...

sacrifice

(Encyclopedia)sacrifice [Lat. sacrificare=to make holy], a type of religious offering, or gift to a superior or supreme being, in which the offering is consecrated through its destruction. The Paleolithic evidenc...

electrolysis

(Encyclopedia)CE5 Electrolysis: In a typical reaction electrodes are placed in a solution of hydrogen chloride, HCl, which contains both hydrogen and chlorine ions. The battery removes electrons from the anode, ...

guided missile

(Encyclopedia)guided missile, self-propelled, unmanned space or air vehicle carrying an explosive warhead. Its path can be adjusted during flight, either by automatic self-contained controls or remote human control...