A comparison of theoretical and experimental limiting slopes for the concentration dependence of thermoelectric powers in dilute aqueous hydrochloric acid and hydrobromic acid

For hydrogen-electrode thermocells with a 10°C temperature difference, initial thermoelectric powers (tep) in dilute (<0.02 mol kg^-1) aqueous solutions of HCl (at mean temperatures of 20, 25, and 30°C) and of HBr (at 15, 25, and 35°C) have been used to determine infinite-dilution limiting slopes of plots of the tep vs. the square root of hydrogen-ion molality. These slopes have been compared with values calculated from a modified heat-of-transport theory and agreement was found to be good.