The negative electrochemical device (NED) is a surface system found in many polycrystalline metal alloy microstructures. NED consists of a multiple electrode galvanic micro-cell with a heterogeneous distribution. Some difficulties for performing experimental work at the microscopic scale and raw interest on technological applications have made NED not much studied in the past, but future nanotechnological applications are making it more interesting to study. The loss of matter on the metal-electrolyte interface due to redox reactions is assessed. Redox reactions have a natural direction to occur, determined by the chemical potential of reactants. Once the reactions occur, there is no way of turning back the oxide species to their original reduced form, meaning that an irreversible entropy has been produced into the system. A new array of the multicomponent Gibbs ensemble is applied and a Young-Laplace equation is proposed for dealing with surface tension. Finally, the mass and entropy interactions are described by the corresponding balance equations. (c) 2007 Elsevier B.V. All rights reserved.