Membrane or Ion-selective Electrode:

There are another category of electrodes called membrane or ion-selective electrodes. These electrodes preferentially respond to a single chemical species. A potential among the indicator electrode and the reference electrode will varies as the concentration or activity of which particular species varies. Different the inert indicator electrodes, ion- selective electrodes do not respond to all species in the solution. Glass membrane electrode or glass electrode is a classical example of ion selective electrodes. Functioning and principle of glass electrode will be discussed in detail in next unit of this course.