Complexation in system Zn(HCO2)2—NH(CONH2)2—H2O at 25℃ and study of physical and chemical properties of the new solid phase

Abstract

The solubility and the nature of the solid phase in the system Zn(HCO2)2—NH(CONH2)2—H2O at 25℃ were investigated by isothermal method. The concentration range of crystallization of the new incongruently soluble compound Zn(HCO2)2 · NH(CONH2)2 · H2O with molar ratio of 1 : 1 : 1 was set in system. The individuality of the new compound Zn(HCO2)2 · NH(CONH2)2 · · H2O was confirmed by chemical, X-ray, differential thermal analysis and IR spectroscopic analysis. It has been shown that, in a complex compound, the coordination of a ligand takes place through an oxygen atom in a carbonyl group. It is shown that the thermolysis of the complex compound is a complex multistage process, which includes stages of complex dehydration and decomposition. The final product of decomposition is zinc oxide. According to X-ray analysis a, b, c, d and hkl unit cell parameters, the value-spacings and intensities of the diffraction patterns of peaks were calculated. The resulting new compound Zn(HCO2)2 · NH(CONH2)2 · H2O has orthorhombic syngony. The composition of the new complex compound set by chemical analysis, matches the theoretically calculated composition and has a constant composition. Refs 4. Figs 3. Tables 2.