Enthalpies of combustion and formation of benzenesulfonamide and some of its derivatives

The energies of combustion of benzenesulfonamide (cr), o-toluenesulfonamide (cr), p-toluenesulfonamide (cr), 2-aminobenzenesulfonamide (cr), and 4-aminobenzenesulfonamide were determined using a combustion rotating-bomb calorimeter. The molar energies of combustion for these compounds in the condensed phase at T = 298.15 K were determined as: −(3611.4 ± 1.8) kJ · mol−1, −(4280.7 ± 1.1) kJ · mol−1, −(4458.8 ± 1.5) kJ · mol−1, −(3745.7 ± 1.2) kJ · mol−1 and −(3725.6 ± 1.9) kJ · mol−1, respectively. From these values, corresponding standard molar enthalpies of formation were obtained as: −(347.1 ± 1.9) kJ · mol−1, −(356.5 ± 1.4) kJ · mol−1, −(178.4 ± 1.7) kJ · mol−1, −(356.9 ± 1.4) kJ · mol−1 and −(377.1 ± 2.1) kJ · mol−1, respectively. A differential scanning calorimeter was used to determine the purities and heat capacities of the compounds studied here. Polyethene bags were used as a combustion auxiliary in the combustion experiments.

► A rotating-bomb calorimeter was used for energies of combustion determinations. ► The energies of combustion of benzenesulfonamides derivatives were determined. ► The standard molar enthalpies of formation of benzenesulfonamides were derived.