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chemical analysis

(Encyclopedia)chemical analysis, the study of the chemical composition and structure of substances. More broadly, it may be considered the corpus of all techniques whereby any exact chemical information is obtained...

isotope

(Encyclopedia)CE5 Isotopes of hydrogen isotope īˈsətōp [key], in chemistry and physics, one of two or more atoms having the same atomic number but differing in atomic weight and mass number. The concept of ...

ozone

(Encyclopedia)ozone ōˈzōn [key], an allotropic form of the chemical element oxygen (see allotropy). Pure ozone is an unstable, faintly bluish gas with a characteristic fresh, penetrating odor. The gas has a dens...

Richards, Theodore William

(Encyclopedia)Richards, Theodore William, 1868–1928, American chemist, b. Germantown, Pa., Ph.D. Harvard, 1888. Richards was a professor at Harvard from 1891 until his death in 1928. In 1914 he received the Nobel...

Bhabha, Homi Jehangir

(Encyclopedia)Bhabha, Homi Jehangir jəhänˌgērˈ bäˈbä [key], 1909–66, Indian physicist, b. Bombay (now Mumbai). He was educated at the Royal Institute of Science, Bombay, and at Cambridge, England, where h...

Meyer, Julius Lothar

(Encyclopedia)Meyer, Julius Lothar, 1830–95, German chemist. He taught at Breslau, Karlsruhe, and Tübingen (from 1876) and is known especially for his work in the development of the periodic law, for which, with...

McMahon, Brien

(Encyclopedia)McMahon, Brien (James O'Brien McMahon), 1903–52, American statesman, b. Norwalk, Conn. After practicing law, he became a judge in Norwalk, and from 1933 to 1936 he served in the office of the U.S. A...

Cockcroft, Sir John Douglas

(Encyclopedia)Cockcroft, Sir John Douglas, 1897–1967, English physicist, educated at the Univ. of Manchester and St. John's College, Cambridge. He was a fellow of St. John's College (1928–46) and professor of n...

nucleus, in physics

(Encyclopedia)nucleus, in physics, the extremely dense central core of an atom. Following the discovery of radioactivity by A. H. Becquerel in 1896, Ernest Rutherford identified two types of radiation given off b...

Archimedes' principle

(Encyclopedia)Archimedes' principle, principle that states that a body immersed in a fluid is buoyed up by a force equal to the weight of the displaced fluid. The principle applies to both floating and submerged bo...