Reconciliation of calorimetrically and spectroscopically derived thermodynamic properties at pressures greater than 0.1 MPa for benzene and methylbenzene: the importance of the third virial coefficient

Thermodynamic properties of pyridine—I. Vapor pressures, high-temperature heat capacities, densities, critical properties, derived thermodynamic functions, vibrational assignment, and derivation of recommended values

“…(12) Test measurements of the density of benzene between T=310 K and T=523 K have been reported. (13) Results agreed with the values published by Hales and Townsend (14) to within 1·10 −3 ·r. The essential features of the ebulliometric equipment and procedures for vapor pressure studies are described in the literature.…”

“…has been described. (13,19) Measured two-phase (liquid+vapor) heat capacities for a minimum of two fillings, vapor pressures, and reliable liquid-density values are required. Table 4 The fitting procedure has been described.…”

“…Table 4 The fitting procedure has been described. (13,19) The C sat,m values determined by adiabatic calorimetry (7) for the temperature range 304Q(T/K)Q347 were included and weighted equally with the vapor pressures. These were included to ensure a smooth junction between the values determined with adiabatic calorimetry and the higher temperature results.…”

“…Experimental methods were described previously. (13,19) Raman and i.r. spectra for the vapor and liquid phases of pyridine were obtained with a Spex 14018 Ramalog spectrophotometer using the 514.5 nm emission of the argon laser and a Digilab FTS-20E instrument, respectively.…”

“…(13,19) The form chosen for variation of the second derivative of the chemical potential with temperature was:…”