Enthalpies of solution of gases in liquids. The calorimeter and measurements on lower hydrocarbons and CO 2 in C 6H 6, CCl 4, and THF

Abstract

An isothermal gas solution calorimeter which yields results under conditions approaching constant volume and temperature is described. Enthalpies of solution of methane, ethane, ethylene, propane, and carbon dioxide in benzene, carbon tetrachloride, and tetrahydrofuran have been determined. Assignments of ΔH o are reported at 288.15 and 298.15 K. The relative precision of the measurements ranged from an optimum of about 1.5 per cent when ΔH o was around 25 kJ mol −1 to 15 per cent when ΔH o was in the 3 to 4 kJ mol −1 range. Comparison of literature data of the redetermined enthalpy of solution of CO 2 in 0.1 mol dm −3 aqueous NaOH ( ΔH o approximately 110 kJ mol −1) indicated that the accuracy was in the 1 to 2 per cent range. The enthalpy of solution of CO 2 in 0.1 mol dm −3 NaOD was measured as (114.6 ± 1.0) kJ mol −1.