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Low-temperature calorimetric measurements were obtained on the condensed phases three alkanediamines, ethylenediamine, (dl)-1,2-propanediamine, and 2-methyl-1,2-propanediamine, as a basis for deriving their heat capacities, Cs, entropies, Ss, thermodynamic functions, −“Gs(T) − Ho(0)’T, “Hs(T) − Ho(0)’T, and Hs(T) − Ho(0), and the enthalpies, entropies, and temperatures of phase transitions. Vapor-pressure measurements were carried out on the above alkanediamines and (dl)-1,2-butanediamine as a means for transforming the condensed-state thermodynamic properties to the perfectgas state at 1 atm. Standard values at 298.15 K were calculated for the enthalpy, Gibbs energy, and equilibrium constant of formation.

Low-temperature thermodynamic properties were measured for cyclopropylamine, cyclopentylamine, and methylenecyclobutane from 12 K to near their respective boiling temperatures. Values of molar heat capacities at saturation pressure of the condensed phases, melting temperatures, purities, and enthalpies of fusion were measured by adiabatic calorimetry. From these measurements the thermodynamic quantities, −{G s (T)−H o (0)} T , {H s (T)−H o (0)} T , { H s ( T )− H o (0)}, S s and C s , were derived for the solid and liquid states. Values at 298.15 K of the standard entropy, standard Gibbs energy of formation, and logarithm of equilibrium constant of formation for the three materials in the ideal-gas state were computed.

Condensed-phase heat capacities and enthalpies were determined at temperatures from near 10 to 400 K for N-methylpyrrole, 2,5-dimethylpyrrole, piperidine, 2-methylpiperidine, 4-methylpyridine, and N-methylcarbazole, and were used to provide the Gibbs energy, enthalpy, entropy, and heat capacity along the vapor-saturation line at temperatures from 0 to 400 K. The corresponding ideal-gas thermodynamic properties were derived using available vapor pressures and enthalpies of vaporization. The Gibbs energy, enthalpy, and entropy of formation were derived for the ideal gas at selected temperatures with available enthalpies of combustion.

Experimental measurements were made of the low-temperature thermal properties of 2-methylheptane and 2-methyldecane from 12 to 360 K and 12 to 390 K, respectively. From these measured values and data from the literature the following chemical thermodynamic properties were calculated at selected temperatures for the condensed phases of 2-methylbutane, 2-methylpentane, 2-methylhexane, 2-methylheptane, and 2-methyldecane: Gibbs energy function, enthalpy function, enthalpy, entropy, and heat capacity. The entropies of 2-methylheptane and 2-methyldecane in the ideal gas state at 298.15 K were calculated and methylene entropy increments obtained for the 2-methylalkanes, C 5 to C 11 .

The low-temperature thermal properties of hexafluorobenzene and 1,3-difluorobenzene were measured by adiabatic calorimetry from 13 to 342 K and 11 to 355 K, respectively. The properties measured were heat capacities of solid and liquid, enthalpies of fusion, triple point temperature, and purity, and, in addition, for 1,3-difluorobenzene, the enthalpy and temperature of a solid-solid transition. From these results the following chemical thermodynamic functions were calculated for the condensed phases at selected temperature: Gibbs energy function, enthalpy function, enthalpy, entropy, and heat capacity. For 1,3-difluorobenzene the entropies in the ideal gas state were calculated at several temperatures, a revised vibrational assignment was made from Raman and infrared frequencies reported in the literature, and the chemical thermodynamic functions in the ideal gas state were calculated from 0 to 1500 K. Values of the Gibbs energy of formation and logarithm of equilibrium constant of formation for 1,3-difluorobenzene were also computed for the range 0 to 1500 K.

Low-temperature calorimetric quantities were determined for acrylonitrile, 1-aminopropane, 2-aminopropane, and 2-methyl-2-aminopropane from 12 K to near their respective normal boiling temperatures. Values of molar heat capacity at saturation pressure of the condensed phases, transition and melting temperatures, and enthalpies of transition and fusion were measured by adiabatic calorimetry. From these data the thermodynamic quantities −{G s (T) − H o (0)} T , {H a (T) − H o (0)} T , {Ha(T) − Ho(0)}, Ss, and Cs were evaluated for the solid and liquid states. For acrylonitrile a revised vibrational assignment was made from Raman and infrared wavenumbers reported in the literature, and a table of thermodynamic functions for the ideal gas state from 0 to 1000 K was prepared. Values of the enthalpy, Gibbs energy, and logarithm of equilibrium constant of formation for acrylonitrile also were computed for the range 0 to 1000 K.

Condensed-phase heat capacities and enthalpies were determined at temperatures from near 10 to 400 K for N-methylpyrrole, 2,5-dimethylpyrrole, piperidine, 2-methylpiperidine, 4-methylpyridine, and N-methylcarbazole, and were used to provide the Gibbs energy, enthalpy, entropy, and heat capacity along the vapor-saturation line at temperatures from 0 to 400 K. The corresponding ideal-gas thermodynamic properties were derived using available vapor pressures and enthalpies of vaporization. The Gibbs energy, enthalpy, and entropy of formation were derived for the ideal gas at selected temperatures with available enthalpies of combustion.