THE THERMODYNAMIC PROPERTIES OF BENZOTHIAZOLE AND BENZOXAZOLE

Measurements leading to the calculation of the ideal-gas thermodynamic properties are reported for benzothiazole (Chemical Abstracts registry number [95-16-9]) and benzoxazole (registry number [273-53-0]). Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c.). Critical-property estimates were made for both compounds. Standard molar entropies, enthalpies, and Gibbs energies of formation were derived for the gas for both compounds for selected temperatures between 280 K and near 650 K. All results obtained in this research are compared with literature values. Literature wavenumber assignments were used to calculate standard molar entropies for both gaseous compounds. Comparison with the calorimetrically derived values shows the need for revision of those assignments. © 1992 Academic Press Limited All rights reserved.