Chemical reactions are described and analyzed using conservation of mass and the law of mass action. The conservation of mass does not imply the conservation of electric current, as can easily be seen by in the reaction A •••• B •••• C where IAB ≠ IBC . The two reactions involve different rate constants, that are customarily independent, so the currents cannot be equal under more than one condition! Electric forces are very very much stronger than diffusion forces: one percent change in net charge produces a force large enough to lift the earth; one per cent change in mass has hardly any effect. I argue that chemical models cannot transferable (with one set of parameters) if they do not satisfy conservation of current. I argue that conservation of current must be exact in models of chemical reactions in all conditions, locations, and times because the ‘current’ defined in Maxwell’s equations cannot be stored, at all. My colleagues and I are trying to construct such models, following the lead of colleagues in semiconductor and computational electronics, who have done this for years.