|the process in which ions are exchanged between a solution and an insoluble solid, usually a resin. It is used to soften water, to separate radioactive isotopes, and to purify certain industrial chemicals|
A reversible chemical reaction between two substances (usually a relatively insoluble solid and a solution) during which ions of equal charge may be interchanged. ion exchange is used in water softening and purification, chemical analysis, the separation of radioactive isotopes, and kidney dialysis. ◇ Cation exchange is the exchange of positively charged ions. ◇ Anion exchange is the exchange of negatively charged ions.