Ion exchange describes a specific chemical process in which unwanted dissolved ions are exchanged fo...........

Explanation:

Ions are atoms or molecules containing a total number of electrons that are not equal to the total number of protons.
There are two different groups of ions, cations, which are positively charged, and anions, which are negatively charged.
Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex. In most cases the term is used to denote the processes of purification, separation, and decontamination of aqueous and other ion-containing solutions with solid polymeric or mineralic "ion exchangers".
Ion exchange is widely used in the food and beverage industry, hydrometallurgy, metals finishing, chemical, petrochemical and pharmaceutical technology, sugar and sweetener production, ground- and potable-water treatment, nuclear, softening and industrial water treatment, semiconductor, power, and a host of other industries.
A typical example of application is preparation of high-purity water for power engineering, electronic and nuclear industries; i.e. polymeric or mineralic insoluble ion exchangers are widely used for water softening, water purification, water decontamination, etc