Enthalpy of solution of tris(2,4-pentanedionato)cobalt(III) in aqueous mixed solvents of 1,4-dioxane and 2-methyl-2-propanol

1987 ◽  
Vol 65 (6) ◽  
pp. 1218-1223 ◽  
Author(s):  
Yasuki Yoshimura
Keyword(s):  
Internal Pressure ◽  
Mole Fraction ◽  
Linear Correlation ◽  
Composition Dependence ◽  
Enthalpy Of Solution ◽  
Excess Enthalpy ◽  
Mixed Solvents ◽  
Hydrophobic Hydration ◽  
System A ◽  
Excess Internal Pressure

The solubilities Xs of tris(2,4-pentanedionato)cobalt(III) (Co(acac)3) in water – 1,4-dioxane (D) and water – 2-methyl-2-propanol (TBA) mixtures were determined over the temperature range of 15–60 °C and 20–43 °C, respectively. These data were fitted to [Formula: see text] and the enthalpy of solution [Formula: see text] of Co(acac)3 was estimated by differentiating the equation. For the water–D system, a linear correlation was found between the excess enthalpy of solution [Formula: see text] of Co(acac)3 and the excess internal pressure [Formula: see text] of the mixtures. [Formula: see text] of Co(acac)3 in the water–TBA mixtures showed complicated composition dependence due to microheterogeneity in the mixtures. The enthalpy of hydrophobic hydration [Formula: see text] of Co(acac)3 in the water–D mixtures was also estimated from the solubility curves and it was found that [Formula: see text] decreased exponentially with decreasing mole fraction of water.

Solubility, enthalpy, and heat capacity of solution of tris(2,4-pentanedionato)cobalt(III) in aqueous mixed solvents of 2-butoxyethanol and 2-ethoxyethanol

1989 ◽  
Vol 67 (12) ◽  
pp. 2108-2115 ◽  
Author(s):  
Yasuki Yoshimura
Keyword(s):  
Heat Capacity ◽  
Linear Correlation ◽  
Composition Dependence ◽  
Enthalpy Of Solution ◽  
Excess Enthalpy ◽  
Mixed Solvents ◽  
The Other ◽  
Aqueous Mixtures ◽  
Heat Capacity Of Solution ◽  
Excess Internal Pressure

The solubility in mole fraction Xs of tris(2,4-pentanedionato)cobalt(III) (Co(acac)3) in aqueous mixtures of 2-butoxyethanol (BE) and 2-ethoxyethanol (EE) has been determined over the temperature range 5–50 °C. From these data, the enthalpy [Formula: see text] and heat capacity of solution [Formula: see text] of Co(acac)3 are estimated by using the Clarke and Glew procedure. For the water–BE system, an approximately linear correlation is found between the excess enthalpy of solution [Formula: see text] of Co(acac)3 and the excess internal pressure δPi of the mixtures at 25 °C. This finding suggests that the composition dependence of [Formula: see text] in this system is mostly governed by the composition dependence of Pi. On the other hand, [Formula: see text] in these mixtures exhibits a characteristic composition dependence and its composition dependence in the water–BE mixtures may be qualitatively explained by considering an effect of the microphase transition which has been shown to occur in the mixture. The composition dependence of both [Formula: see text] and [Formula: see text] in the water–BE mixture is analogous to that in the water–BE mixture and this finding suggests that a microphase formation may also occur in the former mixture. Keywords: tris(2,4-pentanedionato)cobalt(III), temperature dependence of solubility, enthalpy and heat capacity of solution, aqueous mixtures of 2-butoxyethanol and 2-ethoxyethanol, microphase transition.

scholarly journals Verdampfungsgleichgewicht und thermodynamisehe Funktionen des flüssigen Systems Wasser + Essigsäure / Vapour-Liquid. Equilibrium and Thermodynamic Functions of the Liquid System Water + Acetic Acid

1973 ◽  
Vol 28 (10) ◽  
pp. 1740-1742 ◽  
Author(s):  
R. Haase ◽  
M. Pehlke ◽  
K.-H. Dücker
Keyword(s):  
Acetic Acid ◽  
Composition Dependence ◽  
Excess Enthalpy ◽  
Excess Entropy ◽  
Liquid System ◽  
Gibbs Function ◽  
Liquid Equilibrium ◽  
Molar Excess ◽  
C 30 ◽  
System Water

Vapour pressures and vapour compositions of the liquid system water + acetic acid have been measured at 25 °C, 30 °C, 35 °C, 40 °C, and 45 °C in the whole range of compositions. The dimerization of acetic acid in the vapour being taken into account, the molar excess Gibbs function ḠE is derived from the measurements. Earlier measurements of the molar excess enthalpy HE are combined with the -GE values to give the molar excess entropy SE. The “symmetry rule” (Haase, 1951) concerning the composition dependence of ḠE, -HE, and S̄E has been confirmed.

14N- und 15N-NMR-Spektroskopie von Diazaphospholen und die lineare Korrelation der chemischen Verschiebung von zweifach koordiniertem N und P / 14N and 15N NMR Spectroscopy of Diazaphospholes and the Linear Correlation of the Chemical Shift of Two-Coordinate N and P

1986 ◽  
Vol 41 (5) ◽  
pp. 553-559 ◽  
Author(s):  
Alfred Schmidpeter ◽  
Bernd Wrackmeyer
Keyword(s):  
Linear Correlation ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
15N Nmr ◽  
Ground State Structure ◽  
Nitrogen And Phosphorus ◽  
System A ◽  
Nmr Study ◽  
15N Nmr Spectroscopy ◽  
Scalar Relaxation

A systematic natural abundance 15N NMR study of diazaphospholes is presented for the first time, giving accurate values for chemical shifts, δN , and coupling constants J(31P15N), J(15N1H ). 14N NMR spectra can be used to predict the magnitude of 1J( 31P14N) if the broadening of the 31P resonance by scalar relaxation is known. The relaxation behaviour of the 14N nuclei corresponds to that found in azoles indicating a comparable electronic ground state structure. The comparison of the chemical shifts, δN, in the diazaphospholes with δN of corresponding triazoles reveals differences which can be traced to the N-P σ-bonds and to the influence o f the phosphorus atom on the π-system. A linear correlation δN/δP exists coordinate nitrogen and phosphorus, respectively.

Thermodynamics of the dissociation of amino acid in mixed solvents. 2. Glycine in 0.1 mole fraction 1,2-propanediol-water, as 278.15-318.15 K

1989 ◽  
Vol 93 (20) ◽  
pp. 7248-7252 ◽  
Author(s):  
Jiazhen Yang ◽  
Dian Yuan Men ◽  
Chunyu Liang ◽  
Litian Zhang ◽  
Limin He ◽  
...  
Keyword(s):  
Amino Acid ◽  
Mole Fraction ◽  
Mixed Solvents

A new theoretical approach for estimating excess internal pressure

2006 ◽  
Vol 124 (1-3) ◽  
pp. 121-123 ◽  
Author(s):  
Ranjan Dey ◽  
A.K. Singh ◽  
J.D. Pandey
Keyword(s):  
Internal Pressure ◽  
Theoretical Approach ◽  
Excess Internal Pressure

Solvolysis rates in aqueous – organic mixed solvents. V. Kinetics of the alkaline decarboxylation of trichloroacetate ion in water – ethanol solutions

1978 ◽  
Vol 56 (15) ◽  
pp. 2053-2057 ◽  
Author(s):  
El-Hussieny M. Diefallah ◽  
A. M. El-Nadi
Keyword(s):  
Mole Fraction ◽  
Pure Water ◽  
Mixed Solvents ◽  
Activation Parameters ◽  
Solvent Mixtures ◽  
Rate Of Reaction ◽  
Ethanol Addition ◽  
Regular Increase ◽  
Aqueous Organic Mixed Solvents ◽  
Kinetics Of

The kinetics of the alkaline decarboxylation of trichloroacetate ion in ethanol–water solutions have been studied over the temperature range 35.0 to 70.0 °C. The rate of reaction is first order with respect to the trichloroacetate ion and is independent of the concentration of the hydroxide ion. The reactivity is enhanced by increasing the concentration of ethanol in the water–ethanol solutions and the rate of reaction varies with ethanol addition in a nonlinear manner. The rate of reaction increases with the reciprocal of the dielectric constant of the medium and the plot of log k vs. 1/D is approximately linear for solvent mixtures with less than about 0.7 water mole fraction but is strongly curved towards the pure water end. The activation parameters for the reaction show a regular increase in the solvent composition range 0.3 to 1.0 water mole fraction. The results are discussed in terms of the influence of solvent internal pressure and polarity on reactivity and of the increased amount of hydrogen-bonded structure in the water-rich solutions.

scholarly journals Dielectric and Excess Dielectric Constants of Acetonitrile + Butyl Amine, + Ethylamine, and + Methylamine at 303, 313, and 323 K

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Ch. V. V. Ramana ◽  
A. B. V. Kiran Kumar ◽  
M. Ashok Kumar ◽  
M. K. Moodley
Keyword(s):  
Dielectric Constant ◽  
Intermolecular Interactions ◽  
Mole Fraction ◽  
Entire Range ◽  
Binary Systems ◽  
Mixed Solvents ◽  
Dielectric Constants ◽  
Complete Mole ◽  
Butyl Amine ◽  
Mole Fraction Range

The dielectric constants and excess dielectric constants of the binary systems: acetonitrile + butyl amine, + ethylamine and + methylamine have been studied at 303, 313, and 323 K temperatures and over the complete mole fraction range. The dielectric constants for these mixtures were measured using a microcontroller based system. The results are positive over the entire range of composition. Symmetrical curves were observed for the systems in which the maximum occurs approximately at 0.7-mole fraction of acetonitrile. The results are discussed in terms of intermolecular interactions. The investigation of dielectric constant of mixed solvents bearing amines aims at better comprehension of their biological, chemical, pharmaceutical, technological, and laboratory applications.

The impact of temperature change on stress deformed state of a main pipeline surrounded by a viscous medium and affected by thrusts and dislocations of the Earth’s crust

2006 ◽  
Vol 4 ◽  
pp. 32-40
Author(s):  
M.I. Davletov ◽  
Yu.V. Kazantsev ◽  
A.G. Khakimov
Keyword(s):  
Internal Pressure ◽  
Temperature Change ◽  
Viscous Medium ◽  
Earth’S Crust ◽  
Main Pipeline ◽  
Constraint Forces ◽  
Deformed State ◽  
Earth's Crust ◽  
The Impact ◽  
Excess Internal Pressure

The present investigation concerns the movement and stress deformed state of a main pipeline with excess internal pressure surrounded by a highly viscous medium under changing temperature and also in the case of thrusts and dislocations of the Earth’s crust. Account is taken of constraint forces occurred due to excess internal pressure and temperature change.

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