Resistivity of sulphuric-acid solutions and its relation to viscosity and temperature

Abstract

The resistivity of sulphuric-acid solutions ranging from 15 to 45 percent acid has been measured at temperatures of +30 to-40° C, except as the measurements of some solutions were limited by their freezing points. The resistivity of these solutions at 0° C is about 1.7 times that at +30° C, but at-40° C the resistivity is 5.5 times as great. The composition of solutions having minimum resistivity (maximum conductivity) was found to depend on the temperature. At 18 °C the solution having minimum resistivity was found to be 30.4 percent, as previously determined by Kohlrausch, but at-25° C the solution of minimum resistivity contains only 26.5 percent acid. Values of resistivity for each interval of 5 percent in composition and 5° C in temperature are given. An empirical relation between resistivity, kinematic viscosity, and absolute temperature was found to hold for concentrated solutions over a temperature range from +30 to-40° C.