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carboxyl group

(Encyclopedia)carboxyl group kärbŏkˈsĭl [key], in chemistry, functional group that consists of a carbon atom joined to an oxygen atom by a double bond and to a hydroxyl group, OH, by a single bond. Carboxylic a...

chemical bond

(Encyclopedia)chemical bond, mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the for...

fuel

(Encyclopedia)fuel, material that can be burned or otherwise consumed to produce heat. The common fuels used in industry, transportation, and the home are burned in air. The carbon and hydrogen in fuel rapidly comb...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

Attica

(Encyclopedia)Attica ătˈĭkə [key], region of ancient Greece, a triangular area at the eastern end of central Greece, around Athens. According to Greek legend, the four Attic tribes were founded by Ion; in later...

MacKinnon, Roderick

(Encyclopedia)MacKinnon, Roderick, 1956–, American biochemist, b. Burlington, Mass., M.D. Tufts Univ., 1982. MacKinnon was on the faculty at Harvard Medical School from 1989–96 and has been a professor at the H...

Codreanu, Corneliu Zelea

(Encyclopedia)Codreanu, Corneliu Zelea kŏrnĕˈlyo͞o zĕlˈyä kôdrĕäˈno͞o [key], 1899–1938, Romanian political leader and anti-Semitic terrorist. Active in the Romanian student movement against leftists a...

heat exhaustion

(Encyclopedia)heat exhaustion, condition caused by overexposure to sunlight or another heat source and resulting in dehydration and salt depletion, also known as heat prostration. The symptoms are severe headaches,...

cyanogen

(Encyclopedia)cyanogen sīănˈəjən [key], NCCN, colorless, flammable, extremely poisonous gas with a characteristic odor somewhat like that of hydrogen cyanide. It melts at −35℃, boils at −21℃, and is so...

sulfonic acid

(Encyclopedia)sulfonic acid səlfŏnˈĭk [key], organic compound containing the functional group RSO2OH, which consists of a sulfur atom, S, bonded to a carbon atom that may be part of a large aliphatic or aromati...