Comparative kinetic and equilibrium studies on the formation and dissociation of three mono- and one bis-pyridinium-4-aldoxime pentacyanoferrate (II) complexes have been carried out in aqueous solutions at 25° C and I= 0.1 M. The synthesis, spectroscopic and thermal characterization of a new N-methylpyridinium-4-aldoxime pentacyanoferrate (II) complex is presented. The obtained values for the equilibrium constants, identified as apparent ...