skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Pyridine: experimental and calculated chemical thermodynamic properties between 0 and 1500/sup 0/K; a revised vibrational assignment

Conference · · J. Am. Chem. Soc.; (United States)
OSTI ID:7219947

From studies by low temperature calorimetry, comparative ebulliometry, flow calorimetry and combustion calorimetry, values were obtained for the entropy, heat capacity and heat of formation of pyridine in the ideal gaseous state. The calorimetric values of entropy and heat capacity served as guides in revising the vibrational assignments for pyridine and several deuteropyridines. The revised assignment for pyridine and molecular structure data were used in computing values of the thermodynamic functions at selected temperatures between 0 and 1500/sup 0/K Values of the heat, free energy and equilibrium constant of formation were calculated at the same selected temperatures. The experimental investigations provided the following information: values of heat capacity for the solid (13-224/sup 0/K), the liquid (C/sub satd/ = 33.633 - 9.1446 x 10/sup -2/T + 3.8478 x 10/sup -4/T/sup 2/ - 3.3430 x 10/sup -7/T/sup 3/, cal. deg./sup -1/ mole/sup -1/ (240-347/sup 0/K)), and the vapor (C/sub p//sup 0/ = -8.262 + 10.608 x 10/sup -2/T - 5.4662 x 10/sup -5/T/sup 2/, cal. deg./sup -1/ mole/sup -1/ (374-500/sup 0/K)); the heat of fusion (1978.6 cal. mole/sup -1/) at the triple point (231.49/sup 0/K); the entropy of the liquid at 298.16/sup 0/K (42.52 cal. deg./sup -1/ mole/sup -1/); the vapor pressure (log/sub 10/ p(mm.) = 7.04162 - 1374.103/(t + 215.014), (67-153/sup 0/)); the heat of vaporization (..delta..Hv = 13077 - 10.201 T - 4.7941 x 10/sup -3/T/sup 2/, cal. mole/sup -1/ (346-388/sup 0/K)); the second virial coefficient in the equation of state, PV = RT (1 + B/V), (B = -15-84.5 exp (950/T), cc. mole/sup -1/ (346-500/sup 0/K)); and the standard heat of formation of the liquid at 298.16/sup 0/K (23.89 kcal. mole/sup -1/).

Research Organization:
Bureau of Mines, Bartlesville, OK
OSTI ID:
7219947
Journal Information:
J. Am. Chem. Soc.; (United States), Vol. 79; Conference: 130. American Chemical Society meeting, Atlantic City, NJ, USA, Sep 1956
Country of Publication:
United States
Language:
English