روزنامه با شماره پیاپی سال 2003

9

121

129

The heat capacity of copper hydride has been measured in the temperature range 2–60 and 60–250 K using two adiabatic calorimeters. Special procedure for the purification of CuH has been applied and a careful analysis of sample contamination has been performed. The experimental results have been extrapolated up to 300 K due to instability of the copper hydride at room temperature. From the temperature dependence of heat capacity the values of entropy S°(T), thermal part of enthalpy H°(T)−H°(0) and Gibbs function [−(G°(T)−H°(0))] have been calculated assuming S°(0)=0. The standard absolute entropy, standard entropy of formation from the elements and enthalpy of decomposition of copper hydride from the elements have been calculated and found to be 130.8 J K−1 mol−1 (H2), −85.1 J K−1 mol−1 (H2), −55.1 kJ mol−1 (H2), respectively. These new results gave the possibility of discussion on thermodynamic properties of copper hydride. Debye temperature has been for the first time determined experimentally.

Food Microbiology

2003

Food Microbiology