الفهرس 
Aim of the WorkOnly 14 pages are availabe for public view
 |  | from | 203 |  |  |
| | | from | 203 | | |
Abstract
Conductometry was used to evaluate the molecular thermodynamic association parameters for both bulk and nano-vanadyl sulfate in an aqueous solution at different temperatures. The conductivity measurements provided the thermodynamic parameters for the complex formation of the bulk and nano vanadyl with Orange G as a ligand. The calculated Kf and ΔGf for the interaction of the bulk and nano vanadyl sulfate (VOSO4) with Orange G were larger in the 1:1 complex compared to the 1:2 (VOSO4/Orange G) complex in water as a solvent. The complex formation constants decreased with increasing temperature. The more negative ΔGf values of two complexes 1:1 and 1:2 of molecular complexation indicate that the complexation occurs spontaneously and increases with temperature. The negative values of ΔHf referred to an endothermic and entropy-controlled molecular complexation. Molecular docking of vanadyl sulfate versus 7jwy of amino acid of covid-19 allows us to better understand the probable modes of engagement and binding affinities of the targeted molecule (vanadyl sulfate), that provides more clarity on how well the molecules exert bioactivity towards the target. Furthermore, the vanadyl sulfate shows greater antioxidant behavior than ascorbic acid under the same concentration. Vanadyl sulfate can be used as a potent antioxidant because the reduction of its oxygen radicals in the 1.1–1.4 V range results in large reduction peaks. In the presence of the dye Orange G, the hydroelectrochemical behavior of cadmium bromide was investigated to develop conductometric sensors for the detection of these substances, understand their behavior in aqueous solutions, and design an effective method for removing the toxic cadmium ions from contaminated water sources. The conductometric analysis was used to determine the hydroelectrochemical characteristics of the interaction between bulk and nano CdBr2 with Orange G in aqueous solutions at various temperatures. This interaction lowers the conductivity. In contrast to lump CdBr2, nano CdBr2 showed a greater conductivity drop, suggesting that the interaction was more significant. There were two stoichiometric complexes generated, 1:1 and 1:2 (CdBr2/Orange G), the Kf and ΔGf are higher for 1:1 than for 1:2. As the temperature climbed, the formation constants fell and the spontaneity of the reaction increased, as evidenced by the negative sign of ΔGf. While the complex formation was promoted by an increase in molecular disorder, the positive values of entropy (ΔS) proved that the complex formation depended on molecular entropy. The complexation’s exothermic nature was disclosed by the negative values of (ΔHf). These findings can be applied to improve understanding of these materials’ behavior in aqueous solutions and develop effective removal procedures for highly dangerous heavy metal ions from contaminated water sources. We believe that these results contribute to the field and provide a unique perspective on this issue. The cyclic voltammetry of the bulk and nano mercuric chloride (HgCl2) using a multi-walled carbon nano tube electrode was investigated in the absence and presence of Orange G as a ligand in 0.1 M KCl as a supporting electrolyte at 30 oC. The effect of mercuric ion concentration and the scan rates of voltammograms were studied. The cyclic voltammetry results proved that the electrochemical reaction is quasi reversible and diffusion-controlled. The thermodynamic parameters (stability constants, Gibbs free energies, enthalpies and entropies) of the solvation process indicate the complexation of the bulk and nano mercuric chloride with Orange G. The cyclic voltammograms of the bulk and nano cadmium bromide (CdBr2) was studied by using a glassy carbon electrode (GCE) in the absence and in the presence of Crystal violet dye in 0.1 M KCl as a supporting electrolyte at 31 oC. The effect of the bulk and nano cadmium ions concentration and the scan rate of voltammograms were also investigated. The obtained results indicated that the electrochemical reaction is quasi reversible and proceeds with a diffusion-controlled mechanism. Values of the different thermodynamic parameters, stability constants, and Gibbs free energies for the interaction of both the bulk and nano cadmium ions with the dye increased with increasing the dye concentration. This confirmed the formation of more stable complexes.