Conductometric Studies of Ionic Association of Divalent Asymmetric Electrolyte Cu(NO3)2 with Kryptofix -22 in Mixed (MeOH-DMF) Solvents at Different Temperatures

Abstract

On using conductometric technique, new equation is applied for calculation of apparent association constant (KA). The association constant (KA) were studied and calculated for Cu(NO3)2 in absence and presence of Kryptofix-22 (1,7,10,16 tetra oxa 4,13 diaze cyclo octa decane) in mixed (MeOH-DMF) solvents at different temperatures. From the experimental results, the molar conductivities (Λ ) is evaluated. The limiting molar conduclivities (Λ o) were also calculated by using Shedlovsky and Fouss-Kraus extrapolation method. The Gibbs free energies of association (∆ GA) were estimated in absence and presence of Kryptofix-22, and from these date, we calculated ∆ G (Complexing). We also calculated the value of enthalpy (∆ HA) and entropy (∆ SA) For Cu(NO3)2 in absence and presence of Kryptofix-22. In addition to (KA), (∆ GA), (∆ HA), and all the previous results, the molar volume (V), solvated radius (rs), Van der Waals (Vw), electrostriction Volume (Ve) and apparent molar volume ( V φ )were also calculated. All the results were discussed. Keywords Conductometry, Kryptofix-22, Association, Cu(NO3)2, (MeOH-DMF)solvents, Van der Waals volume, Molar solvated volume, Electrostriction volume, Apparent molar volume, Limiting conductance, Free energy of association