In an electric field, cations are attracted to the cathode and anions are attracted to the
anode (Figure 26-20b). Excess cations in the diffuse part of the double layer impart net
momentum toward the cathode. This pumping action, called electroosmosis (or electroendosmosis),
is driven by cations within of the walls and creates uniform pluglike
electroosmotic flow of the entire solution toward the cathode (Figure 26-2la).