Columbia Encyclopedia

Search results

247 results found

free radical

(Encyclopedia)free radical, in chemistry, a molecule or atom that contains an unpaired electron but is neither positively nor negatively charged. Free radicals are usually highly reactive and unstable. They are pro...

Jovian

(Encyclopedia)Jovian (Flavius Claudius Jovianus) jōˈvēən [key], c.331–364, Roman emperor (363–64). The commander of the imperial guard under Julian the Apostate in his Persian campaign, Jovian was proclaime...

alkene

(Encyclopedia)CE5 Alkenes alkene ălˈkēn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon double bonds (see chemical bond). Alkenes with only one double bond h...

alkyne

(Encyclopedia)CE5 Alkynes alkyne ălˈkīn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). Alkynes with one triple bond have t...

WikiLeaks

(Encyclopedia)WikiLeaks: see Assange, Julian.

Péguy, Charles

(Encyclopedia)Péguy, Charles shärl pāgēˈ [key], 1873–1914, French poet and writer. Of a poor, working family, he won scholarships and made a brilliant record as a student. He left the École normale supérie...

electronegativity

(Encyclopedia)electronegativity ĭlĕkˌtrōnĕgətĭvˈətē [key], in chemistry, tendency for an atom to attract a pair of electrons that it shares with another atom (see chemical bond). For example, the molecule...

Ryder, Donald P.

(Encyclopedia)Ryder, Donald P., , 1926-2021, African-American architect, b. Springfield, Oh., Univ. of Illinois (BA, 1951). Ryder was raised in Dayton, Ohio. He serve...

Browse by Subject