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USGS · 70233518

Heat capacities of gibbsite, Al(OH)3, between 13 and 480 K and magnesite, MgCO3, between 13 and 380 K and their standard entropies at 289.15 K, and the heat capacities of Calorimetry Conference benzoic acid between 12 and 316 K

Bruce S. Hemingway·Richard A. Robie·James R. Fisher·William H. Wilson
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Abstract

The heat capacities of gibbsite and magnesite were measured between 13 and 380 K by means of an adiabatic calorimeter. The heat capacity of gibbsite was measured continuously between 340 and 480 K by means of a differential scanning calorimeter. Tables of the thermodynamic functions C° P , (H° T –H° O )/T ,– (G° T –H° O )/T , and S° T –S° O are presented for these phases at integral temperatures. S° T –S° O are 68.44±0.14 J/(K•mol) and 65.09±0.13 J/(K•mol) at 298.15 K for gibbsite and magnesite, respectively. The heat capacities of Calorimetry Conference benzoic acid have been remeasured between 12 and 316 K.

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Bruce S. Hemingway, Richard A. Robie, James R. Fisher, William H. Wilson. 1977. Heat capacities of gibbsite, Al(OH)3, between 13 and 480 K and magnesite, MgCO3, between 13 and 380 K and their standard entropies at 289.15 K, and the heat capacities of Calorimetry Conference benzoic acid between 12 and 316 K. https://pubs.usgs.gov/publication/70233518

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