n. Abbr. e A stable elementary particle in the lepton class having a negative electric charge of 1 elementary unit (about 1.602 × 10-19 coulombs) and a mass of about 9.11 × 10-28 grams. Electrons are found in shells orbiting the nuclei of atoms and can also move freely through space as cathode rays in a cathode-ray tube or as beta particles emitted by radioactive nuclei, or flow in a current through a conducting material impelled by an electric potential difference. [ELECTR(IC) + (I)ON.] |
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