Heat capacity of copper hydride

摘要

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(7), thermal part of enthalpy Hdegrees(7) - Hdegrees(0) and Gibbs function [-(Gdegrees(7) - Hdegrees(0))] have been calculated assuming Sdegrees(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) (H-2), -85.1 J K-1 mol(-1) (H-2), -55.1 kJ mol(-1) (H-2), 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. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 21]