Solvation and complex formation of nickel(II) with benzoic, p-chlorobenzoic, and p-methoxybenzoic hydrazides in aqueous-dioxane media

Solvation and complex formation of nickel(II) with benzoic, p-chlorobenzoic , and p-methoxy-benzoic hydrazides in aqueous-dioxane media were studied. T he mean coordination numbers of water and 1,4-dioxane in Ni(II) solvation c omplexes, the formation constants of mono- and biscomplexes of nickel(II) o f the listed hydrazides at dioxane contents of 0-0.65 mole fraction, as wel l as the free energies of transfer of the ligands from water to aqueous-dio xane solvents were determined. An important role the basicity and solvation of the ligands play in te stability of Ni(II) complexes with benzoic hydra zides was demonstrated.