In order to maintain the solution electroneutrality inside the pit populated by cations released by oxidation in the anodic zone (e.g.,  in case of steel), anions need to migrate inside the narrow pit. It is worth to notice that the electromobilities of thiosulfate () and chloride () anions are the highest after these of  and  ions in aqueous solution. Moreover, the molar conductivity of thiosulfate ions is even higher than that of chloride ions because they are twice negatively charged (weak base reluctant to accept a proton). In capillary electrophoresis, thiosulfate moves faster than chloride and eluates before this latter. The high electromobility of both anions could also be one of the many factors explaining their harmful impact for pitting corrosion when compared with other much less damaging ion species such as  and .