XXV. Variation with oxygen pressure of the thermoelectric power of cadmium oxide

Abstract

Experiments are described which show that (a) over the temperature range240°–570°C, the thermoelectric power of a CdO/Pt couple varies with the absolute temperature T according to the equation dE/dT=-a+b/T the pressure of oxygen in the surrounding atmosphere remaining constant, and (b) at constant temperature the thermoelectric power is a linear function of the logarithm of the oxygen pressure. Simple theory predicts this form of variation but not the correct values of the constants. The quantity b varies smoothly with the oxygen pressure as suggested by A.H. Wilson.