Solid electrolyte cells have been utilized as electrochemical oxygen pumps to supply oxygen to or from electrode-catalyst surfaces. Recently, the use of solid electrolytes to promote catalysis for a number of reactions has been investigated. During these investigations, dramatic increases in the oxygen consumption, far exceeding the amount of oxygen supplied through the O[sup 2]-conducting electrolyte, have been observed accompanying overall increases in reaction rates. In addition, this effect has been recently demonstrated in oxidative reactions using Na[sup +]-conducting as well as proton-conducting solid electrolytes. This phenomenon, named NEMCA (nonfaradaic electrochemical modification of catalytic activity), has been attributed to an effect on chemisorption bonding, and hence the reaction rate constant, by altering the catalyst work function. The conversion of methane to ethane and ethylene is a subject of extensive study by a very large number of research groups in the last 7 years. Attempts to convert methane into useful raw materials by using solid oxide electrolytes have been separately reviewed. Recently, a three-electrode cell using Ag and Ni-Zr electrodes on yttria-stabilized zirconia has been used to study the current-voltate relationship during the oxidation of methane at 600-800[degrees]C. The present communication explores the nonoxidative coupling of methane to C[sub 2] hydrocarbonsmore » over silver electrodes using a solid electrolyte with major conductivity via protons. An added feature of this investigation is the utilization of the electrolyte as a support in a one-chamber reactor rather than a solid oxide membrane partition in a two-chamber reactor. This design, adapted from Otsuka et al., simplifies the overall reactor configuration. Using this type of cell, an attempt is made to connect the nonoxidative coupling of methane with the NEMCA phenomenon. 11 refs., 3 figs., 1 tab.« less