The Complex Ions Formed by Iodine Cyanide with Cyanide and Iodide Ions. The Vapor Pressure, Free Energy and Dissociation of Iodine Cyanide

1933 ◽  
Vol 55 (5) ◽  
pp. 1889-1895 ◽  
Author(s):  
Don M. Yost ◽  
William E. Stone
Keyword(s):  
Free Energy ◽  
Vapor Pressure ◽  
Complex Ions ◽  
Iodide Ions

The effect of pressure on complex ion equilibria

1956 ◽  
Vol 9 (1) ◽  
pp. 54 ◽  
Author(s):  
AH Ewald ◽  
SD Hamann
Keyword(s):  
Free Energy ◽  
Dissociation Constant ◽  
Atmospheric Pressure ◽  
Qualitative Agreement ◽  
Complex Ions ◽  
Cobaltous Chloride ◽  
Iodide Ions ◽  
Effect Of Pressure ◽  
Iodide Ion ◽  
Complex Ion

The effect of pressure on the formation of complex ions in solutions of cobaltous chloride and in solutions containing iodine and iodide has been shown to be in qualitative agreement with a theory (Buchanan and Hamann 1953) attributing these effects primarily to changes in the free energy of salvation of the ions. The dissociation constant of tri-iodide ions in water at 22 �C has been shown to decrease from 1.6 x 10-3 mol kg-1 at atmospheric pressure to 1.2 x mol kg-1 at 1500 atm. The enthalpy of dissociation of the tri-iodide ion was found to be approximately -5 kcal mol-1 and to be little affected by a pressure of 1500 atm.

A vapor pressure method for the simultaneous determination of standard thermodynamic functions of both solutes in a ternary dilute solution

1978 ◽  
Vol 56 (6) ◽  
pp. 844-847 ◽  
Author(s):  
Claude Treiner ◽  
Pierre Tzias ◽  
Marius Chemla
Keyword(s):  
Aqueous Solution ◽  
Free Energy ◽  
Vapor Pressure ◽  
Tetrabutylammonium Bromide ◽  
Ternary Mixtures ◽  
Binary Solvents ◽  
Volatile Components ◽  
Polar Group ◽  
Free Energy Of Transfer ◽  
Energy Of Transfer

It is shown that from vapor pressure measurements on dilute solutions of ternary mixtures with one nonvolatile component, the standard free energy of transfer (ΔGt0) of both solutes from water to aqueous binary solvents can be determined simultaneously. The method is most useful in the case of volatile components. ΔGt0 values are discussed in particular in the case of the transfer of tetrahydrofuran, acetone, and acetonitrile from water to aqueous tetrabutylammonium bromide and urea solutions and compared to the case of the transfer of nonpolar solutes to the same aqueous solution. In each case, the free energy of transfer from water to an aqueous solution of a nonpolar molecule was negative, and introduction in that molecule of a polar group caused the free energy of transfer to be considerably less negative.

scholarly journals A thermometric study on the kinetics of the acid dissolution of aluminium in the presence of Napoleonaea imperialis seeds extract and iodide ions

2018 ◽  
Vol 29 (2) ◽  
pp. 103-109 ◽  
Author(s):  
Habibat Faith Chahul ◽  
Gloria Ihuoma Ndukwe ◽  
David Ogwu Ogwu
Keyword(s):  
Free Energy ◽  
Inhibition Efficiency ◽  
Adsorption Process ◽  
Langmuir Adsorption Isotherm ◽  
Seed Extract ◽  
Considerable Extent ◽  
Acid Dissolution ◽  
Iodide Ions ◽  
Langmuir Adsorption ◽  
Kinetics Of

Abstract The dissolution of aluminum alloy AA 1060 in 0.5 M and 1.0 M HCl was investigated using thermometric measurements. The reaction number of the aluminum coupons varied linearly with the concentration of the acid. Addition of Napoleonaea imperialis seed extract to the dissolving aluminium coupons lowered the reaction number in both concentrations of HCl by inhibiting the dissolution process. The inhibition efficiency of Napoleonaea imperialis seed extract was enhanced to a considerable extent in the presence of iodide ions with the synergistic parameter S > 1. The adsorption of Napoleonaea imperialis extract on the aluminium surface best aligned with the Langmuir adsorption isotherm model. The values of the free energy, ΔGadsfor the adsorption process revealed the process to be spontaneous and physisorptive.

Kinetics and mechanism of oxidation of tris-(1,10-phenanthroline)iron(II) by chlorine and bromine and of the reduction of tris-(1,10-phenanthroline)iron(III) by iodide ions

1979 ◽  
Vol 57 (15) ◽  
pp. 2065-2070 ◽  
Author(s):  
Jide Ige ◽  
J. Folorunso Ojo ◽  
Olusegun Olubuyide
Keyword(s):  
Free Energy ◽  
Ionic Strength ◽  
Activation Parameters ◽  
Chloride Ions ◽  
Reaction Intermediates ◽  
Rate Law ◽  
Iodide Ions ◽  
Good Linear ◽  
Linear Free Energy ◽  
Mechanism Of Oxidation

The rates of the oxidation of tris-(1,10-phenanthroline)iron(II) by chlorine and bromine, and of the reduction of tris-(1,10-phenanthroline)iron(III) by iodide ions have been measured at ionic strength I = 1.0 mol dm−3 (LiClO4). All the reactions obey second-order rate law:[Formula: see text]The activation parameters for the reactions are: Fe(Phen)32+/Br2: ΔH≠ = (64.2 ± 3.2) kJ mol−1, ΔS≠ = −(24.9 ± 1.5) J mol−1 K−1. Fe(Phen)33+/I−:ΔH≠ = (39.8 ± 2.1) kJ mol−1, ΔS≠ = −(19.7 ± 0.8) J mol−1 K−1.The reactions of tris-(1,10-phenanthroline)iron(II) with chlorine and bromine are unaffected by chloride, bromide, and acid. The proposed mechanism for these reactions involves a series of one-electron changes, with the species X2− (X = Cl, Br) as reaction intermediates, since good linear free energy correlations for the primary step, resulting in the formation of X2−, are obtained. The reduction of tris-(1,10-phenanthroline)iron(III) by iodide ions is catalysed by bromide and chloride ions, whereas the reduction of aquoiron(III) by iodide ions is known to be inhibited by bromide and chloride ions. A mechanistic interpretation of this observation is suggested.

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