A class and home problem on electrolyte transport: constant electric field implies electroneutrality, but electroneutrality does not imply a constant electric field
Chemical Physics
2026-05-05 v1
Abstract
We present a class and home problem in graduate transport phenomena and electrochemical engineering that clarifies a common misconception: electroneutrality implies the electric field is constant. Starting with one-dimensional Poisson--Nernst--Planck equations for a silver electroplating cell, students obtain concentration and potential profiles. A companion home problem with added background electrolyte introduces a new dimensionless ratio and admits a closed-form solution. Students conclude that electroneutrality is necessary but not sufficient for a constant electric field.
Keywords
Cite
@article{arxiv.2605.00928,
title = {A class and home problem on electrolyte transport: constant electric field implies electroneutrality, but electroneutrality does not imply a constant electric field},
author = {Ankur Gupta},
journal= {arXiv preprint arXiv:2605.00928},
year = {2026}
}
Comments
11 pages, 4 figures