Excess Heat Capacities of Binary Mixtures Containing o-Chlorotoluene and Pyridine or Isomeric Picolines or Aromatic Hydrocarbons

Abstract

The excess molar heat capacities, C E P À Á 12 , of binary mixtures of o-chlorotoluene (1) with pyridine, a-, b-or c-picoline, benzene, toluene or o-xylene (2) have been measured as a function of composition at 298.15, 303.15 and 308.15 K using a micro differential scanning calorimeter (Model-lDSC 7 Evo). The C E P À Á 12 data have been fitted with the Redlich-Kister equation to calculate binary adjustable parameters along with standard deviations. The sign and magnitude of values of o-chlorotoluene (1) ? pyridine or a-or b-picoline (2) are dictated by the relative proportion of components in the mixtures. However C E P À Á 12 values for o-chlorotoluene (1) ? c-picoline (2) mixture are positive and C E P À Á 12 values for o-chlorotoluene (1) ? benzene or toluene or o-xylene (2) mixtures are negative over the entire mole fraction range. The topology of the constituent molecules has been employed (Graph theory) to determine the C E P À Á 12 data of the studied mixtures. It has been observed that C E P À Á 12 values obtained by Graph theory are in agreement with the experimental values.