NOPR Collection:

Estimation of Inductive Effect PMO Parameters of Methyl & Ethyl Groups from Charge-Transfer Bands of Some π-Molecular Complexes

Wed, 01 Feb 1989 00:00:00 GMT

Title: Estimation of Inductive Effect PMO Parameters of Methyl & Ethyl Groups from Charge-Transfer Bands of Some π-Molecular Complexes Authors: Ghosh, R; Dutta, K K; Mukherjee, A K Abstract: The inductive effect PMO parameters of methyl and ethyl groups have been calculated from the trends in the chargetransfer bands of two series of π-molecular complexes; (i) of methyl- and ethyl-benzenes with iodine monochloride and (ii) of methylated thiophenes with tetracyanoethylene. Coulson-Longuet-Higgins perturbation technique has been applied to obtain expressions for the energies of the donor- MO's in terms of the Hiickel parameters of alkyl groups, and by correlating such expressions linearly with the longest wavelength CT-absorption bands of the molecular complexes, values of the Hiickel parameters of the alkyl groups have been determined. The calculated value for the methyl group is approximately the same for the two series studied and is close to the ones obtained by previous workers. The PMO parameter for ethyl group is found to be less than that for methyl group as expected, since inductive effect decreases with increase in chain-length of the alkyl group. Page(s): 95-97

Flow through Porous Media: Part X-Permeability Studies of Ethylene Glycol, Diethylene Glycol & Their Aqueous Mixtures through Titanium Oxide Membrane

Wed, 01 Feb 1989 00:00:00 GMT

Title: Flow through Porous Media: Part X-Permeability Studies of Ethylene Glycol, Diethylene Glycol & Their Aqueous Mixtures through Titanium Oxide Membrane Authors: Blokhra, R L; Prakash, Chander Abstract: The flow of water, ethylene glycol, diethylene glycol and their aqueous mixtures through a titanium oxide plug has been measured at different temperatures. The results are discussed in terms of' frictional coefficient, which measures the interaction between water and the walls of the membrane. The results are further interpreted in terms of a unit rate process. The values of enthalpy of activation (H^*), entropy of activation (S^*) and free energy of activation (G^*) are determined. The molecular exchange rate K_βɑ between the two phases ɑ and β across the membrane has been reported. Page(s): 98-101

Ion-Pair Association Constants of Alkali & Alkaline Earth Metal Formates in Formic Acid-Acetonitrile Mixtures at 30°C-A Conductance Study

Wed, 01 Feb 1989 00:00:00 GMT

Title: Ion-Pair Association Constants of Alkali & Alkaline Earth Metal Formates in Formic Acid-Acetonitrile Mixtures at 30°C-A Conductance Study Authors: Rao, K Chowdoji; Subha, (Mrs) M C S; Rao, S Brahmaji Abstract: Equivalent conductance values of solutions of lithium, sodium, potassium, calcium and barium formates in 20% formic acid + 80% acetonitrile and 80% formic acid + 20% acetonitrile mixtures have been determined at different concentrations. Fuoss-Kraus and Shediovsky extrapolation methods are used to determine ion-pair association constants (K_a). Reasonable agreement is found between the K_a values obtained by the two methods. Experimentally obtained ion-pair association constants are compared with those calculated using Bjerrum (B), Fuoss (F), Denison & Ramsey (DR) and Ebeling-Kraeft-Yokoyama-Yamatera (EKYY) theories. The results are used to arrive at the type of the ion-pairs and to establish the nature of the ion-solvent interaction. Page(s): 102-105

Ion-Solvent Interactions in Alcohol Rich Binary Mixtures: Densities & Viscosities of Alkali Metal Propionates in Propionic Acid + 1-Propanol Mixtures

Wed, 01 Feb 1989 00:00:00 GMT

Title: Ion-Solvent Interactions in Alcohol Rich Binary Mixtures: Densities & Viscosities of Alkali Metal Propionates in Propionic Acid + 1-Propanol Mixtures Authors: Subha, (Mrs) M C S; Rao, K Chowdoji; Rao, S Brahmaji Abstract: Viscosities and densities of propionates of lithium, sodium and potassium have been measured at 308.15 K in propionic acid (PA) + 1-propanol mixtures containing 5,15 and 30 wt% of propionic acid. The viscosity data have been analysed using the Jones-Dole equation. The activation parameters of viscous flow have been obtained to throw light on the mechanism of viscous flow. The apparent molar volumes (ϕ_v) of these electrolytes at different concentrations have been estimated and the results indicate that these electrolytes behave as structure promoters. Page(s): 106-110