Publication Date |
1978 |
Personal Author |
Ferrante, M. J.; Stuve, J. M.; Daut, G. E.; Pankratz, L. B. |
Page Count |
28 |
Abstract |
Low-temperature heat capacities and high-temperature enthalpies for synthetic Cu2S and CuS were measured. Heat capacities were measured with an adiabatic calorimeter from 5 to 310 K, and resulted in standard entropies at 298.15 K of 27.76 for Cu2S(c) and 16.05 cal/deg mole for CuS(c). Low-temperature values are tabulated for the standard heat capacity, entropy, Gibbs energy function, and enthalpy relative to 0 K. Enthalpies were measured with a copper-block calorimeter from 298.15 to 1,600 K for Cu2S(c,1) and 298.15 to 780 K for CuS(c). The thermal behavior of CuS showed no transitions or other significant anomalies for the low-or high-temperature investigations. Cu2S showed reversible transitions at 376 K with an isothermal heat absorption of 0.865 kcal/mole, 720 K with an isothermal absorption of 0.280 kcal/mole, and approximately 1,400 K with a heat of fusion of 3.070 kcal/mole. High-temperature data are tabulated for the standard heat capacity, entropy, Gibbs energy function, and enthalpy relative to 298.15 K. Enthalpies are also expressed in equation form. The low- and high-temperature data were combined with data from the literature to calculate and tabulate the standard enthalpy and Gibbs energy of formations. |
Keywords |
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Source Agency |
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NTIS Subject Category |
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Corporate Authors |
Bureau of Mines, Albany, OR. Albany Metallurgy Research Center. |
Document Type |
Technical Report |
Title Note |
Rept. of investigations (Final). |
NTIS Issue Number |
197905 |