The kinetics of the reaction of methyl violet with iodide in aqueous methanol system was studied by spectrophotometric method. The rate of reaction of methyl violet in different alcoholic composition in presence of potassium iodide was observed at pH 4 and 6 at various temperatures (298-318 K). Solvatochromic effect was studied in different percentages of methanol (0-50%). Bathochromic shift was observed with the decrease in polarity of solvent. The color change was attributed to molecule's structure, the delocalization of unit electrical charge causes deepening of color and decrease of delocalization causes fading of color due to reduction of dye. Increase in the rate of reaction was observed with increase in alcoholic content and also affected by potassium iodide salt and increased with increase in concentration of potassium iodide. Energy of activation (E a ) and transition energy (E T ) were calculated with the help of kinetic data. Thermodynamic parameters such as enthalpy change of activation (∆H*), Gibbs free energy change of activation (∆G*) and entropy change of activation (∆S*) were evaluated as a function of concentration of solvent and salt.

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The electrical conductance of nickel sulfate (NiSO4.6H2O) solutions in aqueous, aqueous polyvinyl alcohol (PVOH; 0.1, 0.5 and 0.9 g/dL), aqueous methanol (CH3OH) system (30%, v:v) and aqueous PVOH+CH3OH systems were measured in the concentration ranges 0.4×10 -2 to 10×10 -2 mol/L, at different temperatures (298, 303, 308, 313 and 318 K). Ionic interactions of nickel sulfate in aqueous and mixed solvent systems were measured by conductometric analysis. Different relations were used to evaluate conductometric data, for the calculation of molar conductance, molar conductance at infinite dilution (Ʌ°m), degree of dissociation (), dissociation constant (Kd) and Walden product. The increased in Ʌ°m values with the increase in percent composition of aqueous PVOH, show that PVOH interaction with solvents (water and methanol) was higher as compare to PVOH interaction with NiSO4. Solvent effect was also studied by spectrophotometric analysis of NiSO4 in aqueous, aqueous PVOH and aqueous PVOH + CH3OH system. Thermodynamic parameters for dissociation process such as energy of activation (Ea # ), free energy change of activation (ΔGd # ), enthalpy change of activation (ΔHd # ), and entropy change of activation (ΔSd # ) were also calculated as a function of temperature and solvent composition.

Densities of sodium chloride in the concentration range (0.010 to 0.090 ( 0.001) mol • dm -3 have been determined in aqueous and aqueous maltose systems [(1.0, 3.0, 5.0, and 7.0) % w/v] at different temperatures [(298 to 323) K] with the interval of 5 K. Apparent molar volume (φ ν ), partial molar volume (φ ν °) and the ion-ion interaction parameter (S V ) have been calculated, using the Masson equation by applying linear regression analysis. Other parameters were also calculated, viz., transfer volume (φ ν °(tr) ) and partial molar expansibility (φ E °). Values of φ E °show the presence of caging or packing effects. The data obtained from volumetric studies have been used to investigate the ion-solvent interaction and ion-ion interaction. The structure-breaking capacity of sodium chloride has been inferred in aqueous and aqueous maltose systems from Hepler's criterion, i.e., (∂ 2 φ ν °/∂Τ 2 ) Ρ second derivative of partial molar volume with respect to temperature at constant pressure.

This paper presents the effect of polymer (polyvinyl alcohol) on the growth of copper fractal formation. A thin layer electrochemical cell was designed for the study of copper electrodeposition process. The structure and morphology for the copper fractal patterns were investigated by scanning electron microscopy (SEM). The copper fractal dimension was measured by using box counting method. On the basis of diffusion limited aggregation (DLA) model, growth pattern of copper fractal is two dimensional in nature. The copper fractal dimension is affected by the composition of polyvinyl alcohol. The growth pattern of copper fractal formation was measured under constant potential condition.