Columbia Encyclopedia

Search results

500 results found

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.

International Trade Commission, United States

(Encyclopedia)International Trade Commission, United States, independent agency of the U.S. government established in 1916 as the Tariff Commission; renamed International Trade Commission in 1975. It is charged wit...

International Bank for Reconstruction and Development

(Encyclopedia)International Bank for Reconstruction and Development (IBRD) (IBRD), independent specialized agency of the United Nations, with headquarters at Washington, D.C.; one of five closely associated develop...

Atomic Energy Agency, International

(Encyclopedia)Atomic Energy Agency, International (IAEA), independent intergovernmental organization established in 1957 under the aegis of the United Nations to promote safe, secure, and peaceful uses of atomic e...

Foursquare Gospel, International Church of the

(Encyclopedia)Foursquare Gospel, International Church of the, fundamentalist Christian Church and evangelistic missionary body organized in California by Aimee Semple McPherson and Minnie Kennedy in 1927. It derive...

oganesson

(Encyclopedia)oganesson ōˈgənĕsˌən [key], artificially produced radioactive chemical element; symbol Og; at. no. 118; mass number of most stable isotope 294; m.p., b.p., sp. gr., and valence unknown. Situated...

International Fund for Agricultural Development

(Encyclopedia)International Fund for Agricultural Development(IFAD), specialized agency of the United Nations with headquarters in Rome, Italy. IFAD grew out of the 1974 World Food Conference; it was established in...