Thermodynamic Excess Functions for the Liquid System W ater + Acetic Acid from Calorimetric Data

1977 ◽  
Vol 32 (5) ◽  
pp. 507-510 ◽  
Author(s):  
R. Haase ◽  
M. Pehlke
Keyword(s):  
Acetic Acid ◽  
Composition Dependence ◽  
Liquid System ◽  
Pure Liquid ◽  
Excess Functions ◽  
Molar Excess ◽  
Molar Excess Volume ◽  
Thermodynamic Excess Functions ◽  
C 30 ◽  
System Water

Abstract For the liquid system water + acetic acid, we give the results of new calorimetric measurements regarding the molar excess enthalpy H̅E for 25 °C, 30 °C, 35 °C, 40 °C, 55 °C, and 70 °C, covering nearly the entire range of com­ positions. The experimental data show that H̅E is positive for all compositions and temperatures except in the region of low acid concentrations at temperatures below 55 °C where the process of mixing the pure liquid components is exothermic (H̅E<0). Using values of the molar excess Gibbs function G̅E (always positive) derived from earlier data on vapour-liquid equilibria, we compute the molar ex­cess entropy S̅E which is always negative. The “symmetryrule” concerning the composition dependence of G̅E (as compared to that of H̅E and S̅E) has again been confirmed. The composition dependence of S̅E is similar to that of the molar excess volume.

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.

scholarly journals Notizen:Mischungsenthalpien beim flüssigen System Wasser + Essigsäure / Heats of Mixing for the Liquid System Water + Acetic Acid

1972 ◽  
Vol 27 (10) ◽  
pp. 1527-1529 ◽  
Author(s):  
R. Haase ◽  
P. Steinmetz ◽  
K.-H. Dücker
Keyword(s):  
Acetic Acid ◽  
Power Series ◽  
Liquid System ◽  
Heat Of Mixing ◽  
Pure Liquid ◽  
Calorimetric Measurements ◽  
Heats Of Mixing ◽  
Free Parameters ◽  
C 30 ◽  
System Water

Calorimetric measurements of the heats of mixing for the liquid system water+acetic acid at 17 °C, 20 °C, 25 °C, 30 °C, 40 °C, and 50 °C show that there is a change of sign in the function H̅E(x), where H̅E denotes the molar heat of mixing and x the mole fraction of acetic acid. The process of mixing the pure liquid components is weakly exothermic for low acid concentrations, but strongly endothermic for high acid concentrations. The function H̅E can be approximately represented by the usual power series with respect to x, five free parameters at each temperature being necessary.

Zum thermodynamischen Verhalten des flüssigen Systems Wasser + Essigsäure / On the Thermodynamic Behaviour of the Liquid System Water + Acetic Acid

1974 ◽  
Vol 29 (9) ◽  
pp. 1383-1384
Author(s):  
R. Haase ◽  
M. H. Keller ◽  
K.-H. Dücker
Keyword(s):  
Acetic Acid ◽  
Excess Enthalpy ◽  
Excess Entropy ◽  
Liquid System ◽  
Heat Of Mixing ◽  
Gibbs Function ◽  
Molar Excess ◽  
Thermodynamic Behaviour ◽  
Experimental Values ◽  
System Water

Vapour pressures and vapour compositions of the liquid system water+acetic acid have been measured at 50 °C, 55 °C, 60 °C, 65 °C, 70 °C, and 75 °C in the whole range of compositions. The molar excess Gibbs function is derived from the measurements. At 50 °C, where experimental values of the molar excess enthalpy (molar heat of mixing) are available, the molar excess entropy is also given.

Conductivity of the Liquid System Water + Acetic Acid + Silver Acetate

1978 ◽  
Vol 33 (9) ◽  
pp. 1105-1106
Author(s):  
R. Haase ◽  
H. Ben Nasr ◽  
K .-H . Dücker
Keyword(s):  
Acetic Acid ◽  
Ternary System ◽  
Electric Conductivity ◽  
Infinite Dilution ◽  
Liquid System ◽  
Silver Acetate ◽  
Equivalent Conductivity ◽  
Experimental Values ◽  
Limiting Values ◽  
System Water

We present and discuss experimental values of the electric conductivity (and of the density) for the liquid ternary system water + acetic acid + silver acetate at 25 °C. The results given here represent a selection from measurements on more than 200 compositions. The concepts of equivalent conductivity and of limiting values for infinite dilution in the ternary system are also dealt with briefly.

Notizen: Diffusion in the Liquid System Chloroform + Methyl Acetate

1986 ◽  
Vol 41 (11) ◽  
pp. 1337-1338 ◽  
Author(s):  
R. Haase ◽  
W. Engels
Keyword(s):  
Diffusion Coefficient ◽  
Mole Fraction ◽  
Activity Coefficients ◽  
Linear Relation ◽  
Methyl Acetate ◽  
Composition Dependence ◽  
Liquid System ◽  
C 30

We present and discuss the results of measurements of the diffusion coefficient D and the activity coefficients as functions of the mole fraction x of one of the components in the liquid system chloroform + methyl acetate at 10 °C, 30 °C, and 50 °C. The function D(x) exhibits a pronounced maximum at each temperature, while the kinematic diffusion coefficient D*, considered as function of x, shows a flat minimum, its composition dependence being nearer to a linear relation than that of D(x).

Enthalpies of Mixing for the Liquid System Formic Acid + Acetic Acid

1979 ◽  
Vol 34 (5) ◽  
pp. 659-660
Author(s):  
R. Haase ◽  
H.-J. Jansen ◽  
K. Puder ◽  
B. Winter
Keyword(s):  
Acetic Acid ◽  
Formic Acid ◽  
Mole Fraction ◽  
Excess Enthalpy ◽  
Liquid System ◽  
Short Description ◽  
Enthalpies Of Mixing ◽  
Calorimetric Measurements ◽  
C 30 ◽  
Increasing Temperature

Abstract After a short description of the evaluation of the calorimetric measurements, we give the results for the enthalpies of mixing in the liquid system formic acid + acetic acid. The molar excess enthalpy H̄E has been determined as a function of the mole fraction x of acetic acid at 18 °C, 20 °C, 25 °C, 30 °C, and 40 °C. The function H̄E (x) is always positive and nearly symmetric (with a maximum at about x = 0.5) and increases with increasing temperature. A three-parameter fit of the function H̄E (x) has been achieved for each temperature.

Molar excess volumes, isentropic compressions, and isobaric heat capacities of methanol – isomeric butanol systems at 298.15 K

1988 ◽  
Vol 66 (4) ◽  
pp. 713-717 ◽  
Author(s):  
Tsukasa Okano ◽  
Hideo Ogawa ◽  
Sachio Murakami
Keyword(s):  
Hydrogen Bonding ◽  
Concentration Dependence ◽  
Liquid Mixtures ◽  
Heat Capacities ◽  
Excess Volumes ◽  
Pure Liquid ◽  
Excess Functions ◽  
Binary Liquid ◽  
Molar Excess ◽  
Molar Excess Volumes

Molar excess volumes, molar excess isentropic compressions, and molar excess isobaric heat capacities for binary liquid mixtures of methanol with 2-methylpropanol, 2-butanol, and 2-methyl-2-propanol have been determined at 298.15 K. The concentration dependence and magnitude of these thermodynamic functions are quite different from those of the methanol – 1-butanol system, which had been previously determined. Molar excess volumes for two of the present systems are positive over the whole concentration range, except for the 2-methyl-2-propanol system. For the latter system they are negative in the butanol-rich range. Molar excess isentropic compressions of these systems show slightly different concentration dependence from that of the excess volumes, but the order in magnitude resembles that of the excess volumes. Molar excess isobaric heat capacities for all systems are negative and show simple concentration dependence. The minimum values of excess heat capacities are correlated with the magnitude of molar isobaric heat capacities of the pure isomeric butanols. The behavior of these excess functions is discussed with reference to the differences in numbers and strength of hydrogen bonding between the pure liquid and the solution.

Liquid−Liquid Equilibria of the Ternary System Water + Acetic Acid + 1-Heptanol

2000 ◽  
Vol 45 (2) ◽  
pp. 301-303 ◽  
Author(s):  
Adel S. Aljimaz ◽  
Mohamed S. H. Fandary ◽  
Jasem A. Alkandary ◽  
Mohamed A. Fahim
Keyword(s):  
Acetic Acid ◽  
Ternary System ◽  
System Water

Thermodynamische Interpretation der Schmelzdiagramme binärer Systeme aus Methylchlorsilanen und Pyridazin bzw. Pyrazin

1987 ◽  
Vol 42 (4) ◽  
pp. 341-351
Author(s):  
Karl Hensen ◽  
Jens Gaede
Keyword(s):  
Melting Point ◽  
Thermodynamic Functions ◽  
Liquidus Curve ◽  
Optical Measurements ◽  
Miscibility Gap ◽  
Excess Functions ◽  
Cooling Curves ◽  
Acid Base ◽  
Thermodynamic Excess Functions ◽  
Thermodynamic Excess

By analyzing the cooling curves and the resulting melting point diagrams of the chloromethylsilane- pyridazine and pyrazine systems the existence of the incongruently melting addition compounds CH3SiCl3 • Pyridazine, (CH3)2SiCl2 • (Pyridazine)2, (CH3)3SiCl • (Pyridazine)2, CH3SiCl3 • (Pyrazine)2, (CH3)2SiCl2 • (Pyrazine)2 , (CH3)3SiCl • (Pyrazine)2 was proved. By electro-optical measurements of the turbidity point it was proved that the system (CH3)3SiCl- Pyridazine exhibits a miscibility gap which intersects the liquidus curve of the amine. Based on certain approximations it was possible to fit thermodynamic functions to the experimental results to obtain the excess data of mixing of the corresponding systems. These data allow for a more profound understanding of the Lewis-acid base behaviour of the silanes and amines.Chloromethylsilanes, Pyridazine, Pyrazine, Phase Diagrams, Addition Compounds, Thermodynamic Excess Functions

Sign in / Sign up

Export Citation Format

Share Document