Ion I"on ([imac]"[o^]n), n. [Gr. 'io`n, neut, of 'iw`n, p. pr. of 'ie`nai to go.] 1. (Elec. Chem.) an atom or goup of atoms (radical) carrying an electrical charge. It is contrasted with neutral atoms or molecules, and free radicals. Certain compounds, such as sodium chloride, are composed of complementary ions in the solid (crystalline) as well as in solution. Others, notably acids such as hydrogen chloride, may occur as neutral molecules in the pure liquid or gas forms, and ionize almost completely in dilute aqueous solutions. In solutions (as in water) ions are frequently bound non-covalently with the molecules of solvent, and in that case are said to be solvated. According to the electrolytic dissociation theory, the molecules of electrolytes are divided into ions by water and other solvents. An ion consists of one or more atoms and carries one unit charges of electricity, 3.4 x 10^{-10} electrostatic units, or a multiple of this. Those which are positively electrified (hydrogen and the metals) are called {cations}; negative ions (hydroxyl and acidic atoms or groups) are called {anions}.

Note: Thus, hydrochloric acid ({HCl}) dissociates, in aqueous solution, into the hydrogen ion, {H+}, and the chlorine ion, {Cl-}; ferric nitrate, {Fe(NO3)3}, yields the ferric ion, {Fe+++}, and nitrate ions, {NO3-}, {NO3-}, {NO3-}. When a solution containing ions is made part of an electric circuit, the cations move toward the cathode, the anions toward the anode. This movement is called migration, and the velocity of it differs for different kinds of ions. If the electromotive force is sufficient, electrolysis ensues: cations give up their charge at the cathode and separate in metallic form or decompose water, forming hydrogen and alkali; similarly, at the anode the element of the anion separates, or the metal of the anode is dissolved, or decomposition occurs. Aluminum and chlorine are elements prepared predominantly by such electrolysis, and depends on dissolving compounds in a solvent where the element forms ions. Electrolysis is also used in refining other metals, such as copper and silver. Cf. {Anion}, {Cation}. [Webster 1913 Suppl.]

2. One of the small electrified particles into which the molecules of a gas are broken up under the action of the electric current, of ultraviolet and certain other rays, and of high temperatures. To the properties and behavior of ions the phenomena of the electric discharge through rarefied gases and many other important effects are ascribed. At low pressures the negative ions appear to be electrons; the positive ions, atoms minus an electron. At ordinary pressures each ion seems to include also a number of attached molecules. Ions may be formed in a gas in various ways. [Webster 1913 Suppl.]

The Collaborative International Dictionary of English. 2000.

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  • Ion — Ion …   Deutsch Wörterbuch

  • ion — ion·i·cism; ion·i·cize; ion·iza·tion; ion·o·gen; ion·o·gen·ic; ion·og·ra·phy; ion·o·pho·re·sis; ion·o·sphere; ion·oxalis; ion·to·pho·re·sis; man·dil·ion; meth·ion·ic; min·ion·ette; noc·to·vis·ion; opin·ion·able; opin·ion·al; opin·ion·at·ed;… …   English syllables

  • ion — [ jɔ̃ ] n. m. • 1840; angl. ion, du gr. ion, p. prés. de ienai « aller » ♦ Chim., phys. Atome ou molécule qui a perdu sa neutralité électrique par acquisition ou perte d un ou de plusieurs électrons. Ions positifs (⇒ cation) , négatifs (⇒ anion) …   Encyclopédie Universelle

  • ION — steht für in der Chemie oder Physik ein Atom oder Molekül, das elektrisch geladen ist, siehe Ion eine deutsche Nachsilbe, siehe ion Ion ist ein männlicher Vorname, siehe Ion (Vorname) Ion oder ION sind Namen von Personen, Publikationen,… …   Deutsch Wikipedia

  • Ion — 〈n. 27; Phys.; Chem.〉 elektr. geladenes Atom, Atomgruppe od. Molekül [<grch. ion, Part. Präs. von ienai „gehen“, eigtl. „wanderndes (Teilchen)“] * * * Ion [ i̯o:n, auch i:ɔn; griech. ión = Gehendes, Wanderndes (iénai = gehen, wandern)], das; s …   Universal-Lexikon

  • ion — IÓN, ioni, s.m. Atom, moleculă sau grupare de atomi care are un exces de sarcină electrică pozitivă sau negativă. [pr.: i on] – Din fr. ion. Trimis de gall, 14.02.2009. Sursa: DEX 98  IARBA SFÂNTULUI IÓN s. v. salvie de Etiopia. Trimis de siveco …   Dicționar Român

  • -ion — ist ein häufiges Suffix beim Substantiv, das der Wortbildung dient. Inhaltsverzeichnis 1 Herkunft aus dem Lateinischen 2 Herkunft aus dem Griechischen 3 Weblinks …   Deutsch Wikipedia

  • Iön — IÖN, ónis, Gr. ἸἼων, ωνος, (⇒ Tab. XXV.) des Xuthus und der Kreusa, einer Tochter des Erechtheus, Sohn, Apollod. l. I. c. 7. §. 2. Er dienete diesem seinem Großvater in dem Kriege wider die Eleusinier, als atheniensischer Feldherr und schlug… …   Gründliches mythologisches Lexikon

  • Ion — Ion: ION  платформа для создания сверхкомпактных ПК от компании NVIDIA. Ion (менеджер окон)  фреймовый оконный менеджер для UNIX подобных операционных систем. Ion (группа) (исп. Íon) ирландская музыкальная группа, основана в 2005… …   Википедия

  • Ion — Sn (ein elektrisch geladenes Teilchen) per. Wortschatz fach. (19. Jh.) Neoklassische Bildung. Neubildung im Englischen (Faraday) zu gr. ión wandernd , dem neutralen PPräs. von gr. iénai gehen, wandern . Die so benannten Teilchen wandern bei der… …   Etymologisches Wörterbuch der deutschen sprache

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