New solid state heat capacity data for tetracene and pentacene are reported in the temperature range (258 to 600) K. The heat capacity measurements were performed using the step method with a Setaram Micro DSC III calorimeter (Institute of Chemical Technology, Prague) and a Setaram TG-DSC 111 (University of Alberta) calorimeter. These new heat capacity data are shown to be in good agreement with one another and with several solid state constant-pressure heat capacity estimation methods and quantum mechanical calculations. The new results highlight errors in the solid state heat capacity and melting point databases for polynuclear aromatic hydrocarbons.

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Limiting activity coefficients (γ 1 ∞ ) of lower branched alkanols (2-propanol, 2-butanol, 2-methyl-1-propanol, and 2-methyl-2-propanol) in water were measured at several temperatures covering the range from the melting to the normal boiling point of water. Four experimental techniques (namely, headspace analysis, inert gas stripping, Rayleigh distillation, and the method of circulation still) were employed for the purpose. A comprehensive review is further presented of experimental data on the limiting activity coefficients (γ 1 ∞ ), infinite dilution partial molar excess enthalpies (H h 1 E,∞ ), and heat capacities (C h p,1 E,∞ ) of these aqueous solutes. For each alkanol, the compiled data were critically evaluated and together with the data measured in this work correlated with a suitable model equation providing adequate simultaneous description of the equilibrium measurements and the calorimetric information. As a result, a recommended thermodynamically consistent temperature dependence of γ 1 ∞ , H h 1 E,∞ , and C h p,1 E,∞ of superior accuracy was established in the range from the melting point to the normal boiling point of water. In addition, by employing literature data on the respective residual properties of the pure alkanols, analogous recommendations were derived also for the temperature dependence of the Henry's law constants, hydration enthalpies, and hydration heat capacities. Variation of these various infinite dilution thermodynamic properties of aqueous branched alkanols with temperature and alkanol branching is briefly discussed.

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