Spectrophotometric Analysis of Stability Constants of Benzohydroxamic Acid Complexes with Fe(III), Co(II), and Cu(II) at Varying Temperatures

Leena S Ibrahim, Fatima A Khleefa, Hala I Elzubir, Hiam M Osman, Sara H Altayeb, Zizi E. Ahmed

Abstract: This study investigates the stability constants of Fe(III), Co(II), and Cu(II) complexes with benzohydroxamic acid in ethanol at 298.15 K and 318.15 K using the continuous variation method. The results reveal a 1:2 stoichiometric ratio for the Co(II) complex and 1:1 ratios for both Fe(III) and Cu(II) complexes. Calculated stability constants followed the trend Fe > Co > Cu. Thermodynamic parameters suggest that the complexation reactions are endothermic and spontaneous, with large positive entropy changes supporting this interpretation. These findings enhance the understanding of hydroxamic acid coordination with transition metals and their thermodynamic behavior in ethanol media.

Keywords: benzohydroxamic acid, metal complexes, stability constant, spectrophotometry, thermodynamic analysis

How to Cite?: Leena S Ibrahim, Fatima A Khleefa, Hala I Elzubir, Hiam M Osman, Sara H Altayeb, Zizi E. Ahmed, "Spectrophotometric Analysis of Stability Constants of Benzohydroxamic Acid Complexes with Fe(III), Co(II), and Cu(II) at Varying Temperatures", Volume 14 Issue 5, May 2025, International Journal of Science and Research (IJSR), Pages: 663-666, https://www.ijsr.net/getabstract.php?paperid=SR25505195402, DOI: https://dx.doi.org/10.21275/SR25505195402