Calorimetric investigations of a gold-nickel alloy. II. The heat capacity at high temperatures and the entropy of formation

Abstract

The literature of measurements of the heat capacity of alloys is critically reviewed. A Bunsen ice calorimeter is employed to measure the cumulative enthalpy difference between the solid solution Au0.517Ni0.483 and the corresponding weights of the pure metals; differentiation of the temperature curve yields the deviation of the heat capacity of the alloy from the Kopp-Neumann rule. The positive value of this deviation and the large magnitude of the vibrational entropy of solution are related to the loosening of the lattice that accompanies formation of the solid solution.