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International Union of Pure and Applied Chemistry

(Encyclopedia)International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of hum...

formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....

ether, in chemistry

(Encyclopedia)CE5 Ethers ether, any of a number of organic compounds whose molecules contain two hydrocarbon groups joined by single bonds to an oxygen atom. The most common of these compounds is ethyl ether, C...

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...

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 ...

emanation, in chemistry

(Encyclopedia)emanation: see radon.

sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

Brooklyn Bridge

(Encyclopedia)Brooklyn Bridge, vehicular suspension bridge, New York City, southernmost of the bridges across the East River, between lower Manhattan and Brooklyn; built 1869–83. The achievement of J. A. Roebling...

Akashi Kaikyo Bridge

(Encyclopedia)Akashi Kaikyo Bridge, vehicular suspension bridge, S Honshu, Japan, across the Akashi Strait, a busy shipping lane, linking the city of Kobe with Awaji Island and part of a link between Honshu and Shi...

George Washington Bridge

(Encyclopedia)George Washington Bridge, vehicular suspension bridge across the Hudson River, between Manhattan borough of New York City and Fort Lee, N.J.; constructed 1927–31. It is one of the longest suspension...