A conductometric study of dissociation of picric acid in 2-methoxyethanol and 1,2-ethanediol from −10 to 80 °C

Abstract

Dissociation constants of 2,4,6-trinitrophenol (picric acid) in 2-methoxyethanol and 1,2-ethanediol were measured by a conductance method at temperatures ranging from −10 to 80 °C. The determined constants in the two solvents are discussed and are compared on the basis of the physical properties of the solvents, which have been measured at the various temperatures. The dissociation constants show different behaviour with the temperature in the investigated range and they are fitted by equations of the type ln K = A + BT + C/T + D ln T. Furthermore, the thermodynamic functions have been evaluated and discussed.