THE HEAT CAPACITIES OF SILVER, NICKEL, ZINC, CADMIUM AND LEAD FROM − 80° TO 120 °C.

Abstract

The mean heat capacities over 10° intervals from − 80° to 120 °C. have been determined for silver, nickel, zinc, cadmium and lead. The average deviation of the points from a smooth curve was in each case less than 0.1%, and it is believed that the absolute values are not in error by more than this amount.The method used was the adiabatic electric heating of a kilogram or more of the metal in an all-copper jacket.The following equations have been found to fit the curves with maximum deviations of about 0.1%:[Formula: see text]where D(θ/T) is the Debye function and the units are joules per gram per °C.A discussion of the theoretical basis for the equations is given together with some calculations of heat capacities using data (coefficient of expansion, compressibility, etc.) involving no measurements of heat.As a matter of convenience and for purposes of comparison, tables of heat capacities at 10° intervals are given for each metal. Quadratic or linear equations which fit the experimental curves within 0.25% are also given.