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actinide series
(Encyclopedia)actinide series, a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a...metal
(Encyclopedia)metal, chemical element displaying certain properties by which it is normally distinguished from a nonmetal, notably its metallic luster, the capacity to lose electrons and form a positive ion, and th...magnetism
(Encyclopedia) CE5 Lines of induction around a single bar magnet and between opposite poles of different magnets magnetism, force of attraction or repulsion between various substances, especially those made of i...nuclear energy
(Encyclopedia) CE5 Graph of binding energy per nucleon as a function of mass number nuclear energy, the energy stored in the nucleus of an atom and released through fission, fusion, or radioactivity. In these pr...television
(Encyclopedia) CE5 Video transmission and reception of color and black-and-white television: The camera lens focuses collected light rays into mirrors, which separate the image into its three primary color compon...electronic music
(Encyclopedia)electronic music or electro-acoustic music, term for compositions that utilize the capacities of electronic media for creating and altering sounds. Initially, a distinction must be made between the te...ammonia
(Encyclopedia)ammonia, chemical compound, NH3, colorless gas that is about one half as dense as air at ordinary temperatures and pressures. It has a characteristic pungent, penetrating odor. Ammonia forms a minute ...chemistry
(Encyclopedia)chemistry, branch of science concerned with the properties, composition, and structure of substances and the changes they undergo when they combine or react under specified conditions. Organic chemi...dating
(Encyclopedia)dating, the determination of the age of an object, of a natural phenomenon, or of a series of events. There are two basic types of dating methods, relative and absolute. In relative dating, the tempor...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...Browse by Subject
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