The EMF-Temperature Coefficient of "Acid" Standard Cells of the Saturated Cadmium Sulfate Type from 15 to 40° C.

This paper gives the results of new measurements of the effect of temperature on the electromotive force of standard cells of the saturated cadmium sulfate type. Measurements were made over the temperature range of 15 to 40 °C. Twelve cells of NBS manufacture and twenty-four cells supplied by two different commercial manufacturers were used in the studies. Final results were analyzed by the method of least squares using computer programs. The relation between emf and temperature for NBS, company 1, and company 2 cells was found to be given, respectively, by: E t = E 20 ° C - [ 40.44 ( t - 20 ) + 0.921 ( t - 20 ) 2 - 0.00866 ( t - 20 ) 3 ] × 10 - 6 V E t = E 20 ° C - [ 40.14 ( t - 20 ) + 0.888 ( t - 20 ) 2 - 0.00668 ( t - 20 ) 3 ] × 10 - 6 V E t = E 20 ° C - [ 39.28 ( t - 20 ) + 0.986 ( t - 20 ) 2 - 0.00943 ( t - 20 ) 3 ] × 10 - 6 V Values for the entropy and heat-capacity changes for the cell reaction in "acid" standard cells are also given.