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hemoglobin

(Encyclopedia)hemoglobin hēˈməglōˌbĭn [key], respiratory protein found in the red blood cells (erythrocytes) of all vertebrates and some invertebrates. A hemoglobin molecule is composed of a protein group, kn...

compound

(Encyclopedia)compound, in chemistry, a substance composed of atoms of two or more elements in chemical combination, occurring in a fixed, definite proportion and arranged in a fixed, definite structure. A compound...

element

(Encyclopedia)CE5 element, in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compound can be decomposed into its constituent elements by means o...

Hertz, Gustav

(Encyclopedia)Hertz, Gustav go͝osˈtäf hĕrts [key], 1887–1975, German physicist. He is noted for his work on the atom, and he shared with James Franck the 1925 Nobel Prize in Physics for research (1914) on the...

Haas, Arthur Erich

(Encyclopedia)Haas, Arthur Erich häs [key], 1884–1941, American physicist and educator, b. Bohemia. He was professor of physics at Vienna, Leipzig, London, and, from 1936, the Univ. of Notre Dame, South Bend, In...

Wilkinson, Sir Geoffrey

(Encyclopedia)Wilkinson, Sir Geoffrey, 1921–, English inorganic chemist. He shared the 1973 Nobel Prize in Chemistry with Ernst Otto Fischer for their independent research on the organometallic compounds of the t...

charge

(Encyclopedia)charge, property of matter that gives rise to all electrical phenomena (see electricity). The basic unit of charge, usually denoted by e, is that on the proton or the electron; that on the proton is d...

tracer

(Encyclopedia)tracer, an identifiable substance used to follow the course of a physical, chemical, or biological process. In chemistry the ideal tracer has the same chemical properties as the molecule it replaces a...

periodic law

(Encyclopedia)periodic law, statement of a periodic recurrence of chemical and physical properties of the elements when the elements are arranged in order of increasing atomic number. Such an arrangement in the for...

black humor

(Encyclopedia)black humor, in literature, drama, and film, grotesque or morbid humor used to express the absurdity, insensitivity, paradox, and cruelty of the modern world. Ordinary characters or situations are usu...