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  • Ion-exchange reaction | Definition, Examples, Applications, Facts . . .
    Ion-exchange reaction, any of a class of chemical reactions between two substances (each consisting of positively and negatively charged species called ions) that involves an exchange of one or more ionic components Ions are atoms, or groups of atoms, that bear a positive or negative electric
  • Ion-exchange reaction - Procedures, Chemistry, Equilibrium | Britannica
    Ion-exchange reaction - Procedures, Chemistry, Equilibrium: Only rarely are ion exchangers used in stepwise procedures, in which the resin is mixed into a container of solution and then removed for further treatment Much more frequently the exchanger is packed into a tube or column through which the solution is made to flow The column arrangement forces the ion-exchange reaction, which is
  • Ion-exchange reaction - Materials, Process, Applications | Britannica
    Ion-exchange reaction - Materials, Process, Applications: Soil is able to bind positive ions (like K+ and Ca2+) because it contains clay minerals and organic humic acids Both of those substances are insoluble materials that carry, as a part of their molecular framework, negatively charged ionic groups In clays, for instance, such groups are the ends of silicon–oxygen chains—either oxygen
  • Ion-exchange reaction - Applications, Chemistry, Processes | Britannica
    Ion-exchange reaction - Applications, Chemistry, Processes: Ion exchange is used for both analytical and preparative purposes in the laboratory, the analytical uses being the more common An important use of ion-exchange chromatography is in the routine analysis of amino acid mixtures Columns of cation-exchange resin are used, and the solutions are maintained sufficiently acid so that the
  • Ion-exchange reaction - Kinetics, Equilibrium, Processes | Britannica
    Ion-exchange reaction - Kinetics, Equilibrium, Processes: Generally, ion exchange is fast No electron-pair bonds need be broken, and the rate of the process is limited only by the rate at which ions can diffuse in and out of the exchanger structure The openness of the resin structure, however, depends on the degree of its swelling and on its water content When both swelling and water
  • Water softening | Definition, Process, Results | Britannica
    Ion exchange is a common industrial method of water softening It is accomplished by passing the water through columns of a natural or synthetic resin that trades sodium ions for calcium and magnesium ions After the column has been in use for some time, calcium and magnesium begin to appear in the water leaving the column
  • Ion-exchange reaction - Industry, Medicine, Chemistry | Britannica
    Ion-exchange reaction - Industry, Medicine, Chemistry: Ion exchange finds its major industrial application in the treatment of water Hard water—caused by the presence of calcium and magnesium ions, which form insoluble precipitates with soaps—is softened by exchanging its calcium and magnesium ions with sodium ions To accomplish this, the hard water is passed through a column of cation
  • Ion-exchange chromatography | chemistry | Britannica
    Other articles where ion-exchange chromatography is discussed: dating: Technical advances: …by using the methods of ion-exchange chromatography In this process, ions are variously adsorbed from solution onto materials with ionic charges on their surface and separated from the rest of the sample After the dating elements have been isolated, they are loaded into a mass spectrometer and their
  • Rare-earth element - Processing Ores | Britannica
    Ion exchange In the ion-exchange process, a metal ion, R 3+, in solution exchanges with three protons on a solid ion exchanger—a natural zeolite or a synthetic resin —that is normally called the resin The tenacity with which the cation is held by the resin depends upon the size of the ion and its charge
  • Ion-exchange resin | Synthetic Polymer, Adsorption Properties | Britannica
    Ion-exchange resin, any of a wide variety of organic compounds synthetically polymerized and containing positively or negatively charged sites that can attract an ion of opposite charge from a surrounding solution The resins commonly consist of a styrene-divinylbenzene copolymer (high molecular





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