The Electrical Conductivity of Chlorinated Hydrocarbons

A series of experiments on chloroform and chlorobenzene of unusual purity have shown that the d-c conductance of liquid semi-insulators depends in a complicated way upon the impurities present (including air) and upon the material of the cell electrodes. Effects at the electrodes are split into ohmic, concentration, and activation polarizations, and these three parts are separated experimentally. The final conductances obtained with four different electrode metals were: chlorobenzene, 1.1 × 10-11 ohm-1-cm-1 (centimeter); chloroform, 1.0×10-11 ohm-1-cm-1. These low values were achieved in an evacuated circulating still with no pre-electrolysis; even lower conductances are possible.