Coion Exclusion

In a cation exchange membrane, due to the system electroneutrality, the fixed anions are in equilibrium with mobile cations (referred to as counterions). In contrast, anions functioning as co-ions are more or less excluded from the membrane because their charge is identical to the fixed ion charge. This phenomenon, known as the Donnan exclusion of co-ions or electrolytes, enables the ideal membrane to transfer cations only. In the same way cations are excluded from the anion exchange membrane. The Donnan exclusion equilibrium, and thus the membrane selectivity, depends quantitatively on the concentration of the fixed ions, the valence of co- and counterions, the concentration of an equilibrating external solution, and the affinity of the exchange groups to respective counterions.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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