Journal of Chemical and Engineering Data, Vol.50, No.1, 164-172, 2005
Low-temperature heat capacities and derived thermodynamic functions of 1,4-dichlorobenzene, 1,4-dibromobenzene, 1,3,5-trichlorobenzene, and 1,3,5-tribromobenzene
The heat capacities of 1,4-dichlorobenzene, 1,4-dibromobenzene, and 1,3,5-trichlorobenzene from 5 K to 380 K and 1,3,5-tribromobenzene from 5 K to 410 K were measured by adiabatic calorimetry. The experimental data were used to calculate the molar entropy and enthalpy values relative to 0 K. Apart from 1,4-dichlorobenzene, the substances do not show any solid-solid transitions. Molar enthalpies of fusion and melting-point temperatures were determined. The results, given in order, are (17 907 +/- 15) J(.)mol(-1) and (326.24 +/- 0.03) K, (20 387 +/- 15) J(.)mol(-1) and (360.48 +/- 0.03) K, (17 557 +/- 35) J(.)mol(-1) and (335.92 +/- 0.03) K, and (21721 +/- 20) J(.)mol(-1) and (394.96 +/- 0.07) K.