J Mater Sci Technol ›› 2005, Vol. 21 ›› Issue (01): 140-144.

• Research Articles • Previous Articles    

Physical Studies of Some Hydrazinobenzoic Acid Complexes

M.G.Abd El Wahed, S.Abd El Wanees, M.El Gamel, S.Abd El Haleem   

  1. Faculty of Science, Zagazig University, Zagazig, Egypt
  • Received:1900-01-01 Revised:1900-01-01 Online:2005-01-28 Published:2009-10-10
  • Contact: M.G.Abd El Wahed

Abstract: The stability constants of complexes of 2-hydrazinobenzoic acid and 4-hydrazinobenzoic acid with Ni (II), Cu (II), Zn (II), Cd (II), and Hg (II) were determined potentiometrically at different temperatures. The thermodynamic parameters, △G0, △H0, and △S0 were calculated and proved that the complexation process is spontaneous and endothermic. The thermodynamic functions were analyzed in terms of electrostatic and non-electrostatic components and the results reveal that ionic bonds are formed between the studied ligands and metal ions. Conductometric titration was shown that the stoichiometry of the formed complexes are M:L and M:2L. The structure of the prepared solid complexes was characterized using IR, 1H NMR, 13C NMR spectroscopies as well as X-ray diffraction technique. Finally electrical conductivity of the ligands and their copper complexes was measured and shown that the ligands have a semiconductor behaviour.

Key words: Potentiometric titration, Stability constants, Thermodynamic parameters...