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1.
In this paper, excess thermodynamic functions have been computed from the measured values of density, viscosity, and refractive index at T = (298.15, 303.15, and 308.15) K, ultrasonic velocity at T = 298.15 K over the entire mixture composition range of (anisole with ethanol, propan-1-ol, propan-2-ol, butan-1-ol, pentan-1-ol, or 3-methyl butan-1-ol). Excess molar volume, VE has been calculated from densities, whereas deviations in viscosity, Δη, were computed from the measured viscosities. From ultrasonic velocities, isentropic compressibilities were calculated, from which deviations in isentropic compressibility, Δks have been computed. Lorenz-Lorentz mixture rule was used to compute molar refractivity, R from refractivity index data and from these data, deviations in molar refractivity, ΔR have been computed. Computed thermodynamic quantities have been fitted to Redlich and Kister polynomial equation to derive the coefficients and standard errors between experimental and predicted quantities. Intermolecular interactions between anisole and alkanols have been studied based on the computed excess thermodynamic quantities.  相似文献   

2.
Excess molar enthalpies, $ H_m^E $ of N , N -dimethylacetamide + methanol, + ethanol, + propan-1-ol, + butan-1-ol, + pentan-1-ol, and + hexane-1-ol have been determined at 298.15 K and atmospheric pressure using a Parr 1455 solution calorimeter. While the excess molar enthalpies are negative for methanol and ethanol mixtures, those for propan-1-ol, butan-1-o1, pentane-1-ol, and hexan-1-ol mixtures are positive over the entire range of composition of N , N -dimethylacetamide. The $ H_m^E $ at around x , 0.5 follow the order: methanol<ethanol<propan-1-ol<butan-1-ol<pentan-1-ol<hexan-1-ol. The results are explained in terms of the self-association exhibited by the alkan-1-ols and the formation of aggregates between unlike molecules through OHO hydrogen bonding. The experimental results for mixtures are well represented by the Redlich - Kister equation.  相似文献   

3.
Journal of Solution Chemistry - Excess molar enthalpies, $${H}_{\text{m}}^{\text{E}}$$ of binary mixtures of monoethanolamine (MEA) with propan-1-ol, butan-1-ol, pentan-1-ol and hexan-1-ol were...  相似文献   

4.
Abstract

Isentropic compressibility data, KS of 1,2-Dibromoethane + Propan-1-ol, + butan-1-ol, + pentan-1-ol, hexan-1-ol, heptan-1-ol and octan-1-ol at 303.15 K are reported. Deviations in isentropic compressibility, KS values are found to be negative for mixtures of 1,2-dibromoethane with propan-1-ol over the entire range of composition and while in butan-1-ol the δKS values are negative at lower molefractions and positive at higher molefractions. Therefore as the chain length increases it is showing the positive deviations. The data are interpreted in terms of specific interactions between the components.  相似文献   

5.
Excess molar enthalpies, HE for the binary systems formamide+methanol, + ethanol, + propan-1-ol, + butan-1-ol, + pentan-1-ol, and + hexan-1-ol have been measured at 298.15 K and atmospheric pressure with a Paar 1455 solution calorimeter. All the system present endothermic events and showed maximum positive HE values around 0.40-0.50 mole fraction of formamide. The HE values increases in the order: methanol<ethanol<propan-1-ol<butan-1-ol<pentan-1-ol<hexan-1-ol. Experimental showed insolubility of hexan-1-ol in formamide around x≅0.5 mole fraction of formamide. The excess enthalpies of the above mentioned binary systems, were used to discuss interaction between the alkan-1-ols and formamide molecules. The results are interpreted to gain insight into the changes in molecular association equilibria and structural effects in these systems through O···HO hydrogen bonding. The experimental data have been correlated using Redlich-Kister polynomials. In this research work, the thermodynamics models were also tested: NRTL, Wilson models and their parameters were calculated. The correlation of excess enthalpy data in the systems using NRTL model provides good results.  相似文献   

6.
Densities (ρ)of the binary systems of {difurylmethane + (ethanol or propan-1-ol or butan-1-ol or pentan-1-ol or hexan-1-ol)} have been measured with an Anton Paar DMA 4500 vibrating-tube densimeter over the entire composition range at 298.15,K and atmospheric pressure. Excess molar volumes (V m E ) of each binary system were determined and correlated by the Redlich-Kister equation. Limiting (V i E,∞) and excess partial molar volumes (V i E ) of components of each binary system have been calculated to provide insight into the intermolecular interactions present and the packing efficiencies. The results have been discussed in terms of specific intermolecular interactions, dispersive forces and structural effects.  相似文献   

7.
The densities and speeds of sound in the pentan-1-ol + nonan-1-ol, pentan-1-ol + dekan-1-ol, propan-1-ol + hexan-1-ol, and propan-2-ol + hexan-1-ol binary systems have been measured within the whole composition range at 298.15 K. The quantities determined from the measurement data have been plotted as functions of composition. The excess molar volumes have been interpreted on the basis of results of the Symmetrical Extended Real Associated Solution Model (S-ERAS).  相似文献   

8.
    
Ultrasonic sound velocities and densities of binary mixtures of 1-bromobutane with propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol, heptan-1-ol and octan-l-ol have been experimentally determined at 303·15 K. Isentropic compressibilities (K s) and deviations in isentropic compressibilities (ΔK S) have been calculated from the results. The values of ΔKS are almost positive over the entire range of composition in all six binary liquid mixtures. The experimental results are explained in terms of depolymerisation of hydrogen-bonded alcohol aggregates, decrease in dipolar association and weak hydrogen-bonding interaction of the type Br---H-O between unlike molecules.  相似文献   

9.
The densities of propan-2-ol + pentan-1-ol, + hexan-1-ol, + heptan-1-ol, + octan-1-ol + nonan-1-ol and speeds of sound in propan-2-ol + pentan-1-ol, + heptan-1-ol, + nonan-1-ol have been measured over the whole composition range at 298.15 K. Excess molar functions determined from the experimental data have been plotted as functions of composition. The excess molar volumes have been interpreted on the basis of the Symmetrical Extended Real Associated Solution Model (S-ERAS).  相似文献   

10.
The kinematic viscosity of n-nonane mixtures with propan-1-ol, butan-1-ol, and pentan-1-ol was measured over the temperature range 293.15–313.15 K. For all systems, negative deviations of viscosity from additive values were obtained; the deviations increased in magnitude as the temperature and alkan-1-ol hydrocarbon radical length increased. The activation energy of viscous flow was calculated in terms of the Eyring theory and free volume theory in the usual and extended (with the inclusion of molecular association) variants at equimolar mixture compositions. The behavior of the concentration dependences of viscosity and the activation energy of viscous flow in alkan-1-ol-n-alkane mixtures was found to be controlled by molecular association processes.  相似文献   

11.
In view of industrial importance of binary {ethyl alcohol + (propan-1-ol/propan-2-ol)} mixtures, the densities (ρ) and refractive indices (n D ) of these alkanols mixtures were measured for different compositions at 303.15 K. Molar volumes (V m) and excess molar volumes (V E) of these binary mixtures were calculated from experimental density data of pure solvents and solvents mixtures. The measured refractive index and density data was used to calculate specific refractions (R D ), molar refractions (R M) and apparent molar refractions (R φ, i ) of binary mixtures. From mole fraction dependence of apparent molar refractions, the limiting apparent molar refractions (R φ, i ) of propan-1-ol and propan-2-ol have been determined. The graphical values of R φ, i for propan-1-ol and propan-2-ol were found to be 9.5664 and 7.405 cm3 mol?1 respectively. Structural changes, geometrical fittings and molecular interactions in binary mixtures of these alkanols have been discussed.  相似文献   

12.
Excess molar enthalpies and heat capacities of binary mixtures containing dimethyl sulfoxide (DMSO) + seven normal alkanols, namely methanol, ethanol, propan-1-ol, butan-1-ol, hexan-1-ol, octan-1-ol, and decan-1-ol, have been determined at 303.15 K and atmospheric pressure. With the exception of the DMSO-methanol system, which shows negative values, all mixtures show positive values of excess molar enthalpies over the whole range of mole fraction, increasing as the number of carbon atoms increases. Heat capacities of pure components have been determined in the range 288.15 < T (K) < 325.15. Molar heat capacities of the mixtures are always positive and decrease as the number of carbon atoms decreases. The results were fitted to the Redlich-Kister polynomial equation. Molecular interactions in the mixtures are interpreted on the basis of the results obtained.  相似文献   

13.
The density, viscosity and speed of sound of pure p-anisaldehyde and some alkanols, for example, methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, butan-2-ol, 2-methylpropan-1-ol, and the binary mixtures of p-anisaldehyde with these alkanols were measured over the entire composition range at 303.15 K. From the experimental data, various thermodynamic parameters such as excess molar volume (VE), excess Gibbs free energy of activation (ΔG*E), and deviation parameters like viscosity (Δη), speed of sound (Δu), isentropic compressibility (Δκs), are calculated. The excess as well as deviation parameters are fitted to Redlich—Kister equation. Additionally, the viscosity data for the systems has been used to correlate the application of empirical relation given by Grunberg and Nissan, Katti and Chaudhari, and Hind et al. The results are discussed in terms of specific interactions present in the mixtures.  相似文献   

14.
The viscosity deviation (Δη), the excess molar volume (V E) and the ultrasonic speed (u) have been investigated from viscosity (η) and density (ρ ) measurements of binary liquid mixtures of 1,2-dimethyoxyethane with methanol, ethanol, propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol or octan-1-ol over the entire range of composition at 298.15 K. The excess volumes are negative over the entire range of composition for all of the mixtures with the exception of hexan-1-ol and octan-1-ol. The excess isentropic compressibilities (K S E) and viscosity deviations are negative for all of the mixtures. The magnitudes of the negative values of V E decrease with the number of carbon atoms of the alkan-1-ol. The trend of increasing K S E values with the chain length of the alkanol is similar to that observed in the case of V E. Graphs of V E, Δ η, K S E, Δ u, L f E and Z E against composition are presented as a basis for a qualitative discussion of the results.  相似文献   

15.
The kinetics of oxidation of a series of alcohols (propan-2-ol, 2-methylpropan-1-ol, butan-1-ol, butan-2-ol, 3-methylpentan-1-ol, heptan-4-ol, decan-2-ol, cyclohexanol, borneol) by chlorine dioxide in organic solvents was studied using spectrophotometry. The reaction is described by the second-order rate equation w = k[ROH][ClO2]. The rate constants were measured in the range of 10–60 °C, and the activation parameters of the processes were calculated. The products were identified, and the yields were determined.  相似文献   

16.
Excess molar volumes VmEatT =  298.15 K and atmospheric pressure are reported for (N -methyl-2-pyrrolidinone  +  propan-2-ol, or butan-1-ol, or butan-2-ol, or 2-methylpropan-1-ol ). TheVmE have been calculated from measured values of density using the vibrating tube technique. The results are discussed in terms of the hydrogen bonding and other intermolecular association. Excess molar enthalpiesHmE at T =  298.15 K and atmospheric pressure are reported for (N -methyl-2-pyrrolidinone  +  propan-1-ol, or propan-2-ol, or butan-1-ol, or butan-2-ol, or 2-methylpropan-1-ol). The HmEhave been obtained using flow calorimetry. The experimental results have been correlated and compared with the results from the Extended Real Associated Solution (ERAS) theory. The parameters adjusted to the mixtures properties are two cross association parameters and the interaction parameter responsible for the exchange energy of the van der Waals interactions. Self-association parameters of the alcohols and NMP are taken from the literature.  相似文献   

17.
Novel quaternary ammonium ionic liquid, ethyl(2-hydroxyethyl)dimethylammonium bis(trifluomethylsulfonyl)imide (C2NTf2), has been prepared from N,N-dimethylethanolamine as a substrate. The paper includes a specific basic characterization of the synthesized compound by NMR and the basic thermophysical properties: the melting point, enthalpy of fusion, enthalpy of solid-solid phase transition, glass transition determined by the differential scanning calorimetry (DSC), temperature of decomposition, and water content. The density of the new compound was measured. The solid-liquid or liquid-liquid phase equilibria of binary mixtures containing {C2NTf2+water or an alcohol (propan-1-ol, butan-1-ol, hexan-1-ol, octan-1-ol, decan-1-ol), aromatic hydrocarbons (benzene, toluene), aliphatic hydrocarbons (n-hexane, n-octane), dimethylsulfoxide (DMSO), or tetrahydrofuran (THF)} have been measured by a dynamic method in a wide range of temperatures from 230 to 430 K. These data were correlated by means of the nonrandom two-liquid (NRTL) equation utilizing temperature-dependent parameters derived from the solid-liquid or liquid-liquid equilibrium. From the solubility results, the negative value of the partition coefficient of ionic liquid in binary system octan-1-ol/water (log P) at 298.15 K has been calculated.  相似文献   

18.
Densities, ρ, of the binary systems {difurylmethane + (ethanol or propan-1-ol or butan-1-ol or pentan-1-ol or hexan-1-ol)} have been measured with an Anton Paar DMA 4500 vibrating-tube densimeter over the entire composition range at 288.15 and 308.15 K and atmospheric pressure. The measured and literature densities of [difurylmethane + n-alkanol] binary systems have been used to check the validity of the relationship describing the dependence of density on composition. This relation is useful for obtaining interpolated ρ values corresponding to the experimental data. Excess molar volumes (V mE) of each mixture, limiting (V m,i E,∞) and excess partial (V m,i E) molar volumes and the limiting partial molar expansion (E p,i ) of both components of each binary system have been examined to provide insight into the temperature variations of the intermolecular interactions and molecular packing efficiencies. The results have been discussed in terms of specific intermolecular interactions and structural effects.  相似文献   

19.
The kinetics of the oxidation of a series of alcohols (viz., ethanol, propan-2-ol, butan-1-ol, butan-2-ol, heptan-4-ol, decan-2-ol, propan-1,3-diol, butan-2,3-diol, cyclohexanol, benzyl alcohol, and borneol) with the oxoammonium salt 2,2,6,6-tetramethylpiperidine-1-oxyl chlorite in acetonitrile was studied by spectrophotometry. The products of oxidation of primary alcohols are the corresponding aldehydes and carboxylic acids, and the products of oxidation of secondary alcohols are ketones. The reaction rate is described by the second order equation. The rate constants and activation parameters were determined. The rate constant as a function of the alcohol nature is described by the one-parameter Taft equation.  相似文献   

20.
The molecular structure of 2,2,4,4-tetramethyl-3-(3,4,5-trimethoxyphenyl)pentan-3-ol, C18H30O4, has been determined from 3-dimensional X-ray data. The monoclinic unit-cell, P21/c with a = 14.420(6), b = 8.629(4) and c = 15.003(6) Å and β = 109.45(3)°, contains four molecules. Refinement converged to a final conventional R-index 4.6% for 2662 observed reflexions.The orientation of the C(OH)-t-Bu2 group and the OMe groups with respect to the benzene nucleus is discussed and compared with the orientations found in related compounds.  相似文献   

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