Thermodynamics of lead(II) halide complex formation in calcium nitrate tetrahydrate - Acetamide melts

The complex formation between lead(II) ions and chloride and bromide ions in melts of Ca(NO3)(2 .) 4H(2)O . aCH(3)CONH(2) has been studied at different temperatures between 30 and 70 C. The formation constants of the complexes PbX+ and PbX2 (X = Cl, Br) were determined from emf measurements by means of Ag/AgX electrodes. The dependence of the formation constants for PbCl+ on the solvent melt composition has been analysed. The thermodynamic parameters DeltaH(11)(0) and DeltaS(11)(0) for PbX+ complex formation have been estimated. The parameters are compared with the literature data for the same process in dilute aqueous solutions and in some hydrated and anhydrous salt melts.