Calorimetric Study of Mg2Zn3

The thermodynamic properties of Mg Zn were investigated by calorimetry. The standard entropy of formation at 298 K, , was determined from measuring the heat capacity, , from near-absolute zero (2 K) to 300 K by the relaxation method. The standard enthalpy of formation at 298 K, , was determined by solution calorimetry in hydrochloric acid solution. The standard Gibbs energy of formation at 298 K, , was determined from these data. The results obtained were as follows: = –69.80 ±20 kJ · mol ; = –10.95 ± 1.80 J · K · mol ; = –66.55 ± 20 kJ · mol . The electronic contribution to the heat capacity of Mg Zn was found to be similar to pure magnesium, indicating that the density of states in the vicinity of the Fermi level follows the free-electron parabolic law.