The standard molar enthalpy of formation of 2,3-dichlorodibenzo-p-dioxin

T.S. Papina, V.P. Kolesov, V.A. Lukyanova, V.F. Golovkov, C.A. Chernov, V.P. Vorobieva

J. Chem. Thermodynamics (in print)

ABSTRACT.The standard molar enthalpy of combustion of crystalline 2,3-dichlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry to be equal to (5406.4 +- 6.6) kJ/mol. Using this result and the standard enthalpy of sublimation, (108.6 +- 1.0) kJ/mol, the values of the standard molar enthalpies of formation of 2,3-dichlorodibenzo-p-dioxin in the crystalline and gaseous states were found to be -(220.5 +- 6.8) kJ/mol and -(111.9 +- 6.9) kJ/mol, respectively. The standard molar enthalpy of formation of 2,3,7,8- tetrachlorodibenzo-p-dioxin was estimated as equal to -164.6 kJ/mol.

Laboratory of Thermochemistry