scholarly journals Prediction of Solvatochromic Polarity Parameters for Aqueous Mixed-Solvent Systems

2020 ◽  
Vol 10 (23) ◽  
pp. 8480
Author(s):  
Alif Duereh ◽  
Amata Anantpinijwatna ◽  
Panon Latcharote
Keyword(s):  
Predictive Model ◽  
Mixed Solvent ◽  
Solvent Polarity ◽  
Aqueous Mixtures ◽  
Hydrogen Bond Donor ◽  
Ideal Model ◽  
Solvent Systems ◽  
Relationship Of ◽  
Electronic Transition Energy ◽  
Polarity Parameters

Solvent polarity is important data being used in solvent selections for preliminary engineering design of chemical processes. In this work, a predictive model is proposed for estimating the solvatochromic polarity of electronic transition energy (ET) of Reichardt indicator for aqueous mixtures. To validate the model, the ET values of eighteen aqueous mixtures collected from the literature were used. The predictive model provided a good estimation of ET values with an overall deviation of 2.1%, compared with an ideal model (5.1%) from the mole fraction average. The linear relationship of the contribution factor of hydrogen bond donor interactions (CFHBD) in the predictive model with Kamlet–Taft acidity was newly proposed in order to extend the model for other aqueous mixtures. The predictive model is applicable to many aqueous mixtures and simply requires three properties of pure components as: (i) ET values, (ii) gas-phase dipole moment and (iii) Kamlet–Taft acidity.

Solute–solvent effects in the dissociation of thymolsulfonephthalein (an uncharged acid) in aqueous mixtures of acetonitrile (ACN), urea, and dimethyl sulfoxide (DMSO)

1986 ◽  
Vol 64 (8) ◽  
pp. 1521-1526 ◽  
Author(s):  
A. L. De ◽  
A. K. Atta
Keyword(s):  
Solvent Effect ◽  
Dimethyl Sulfoxide ◽  
Solvent Effects ◽  
Mixed Solvent ◽  
Dissociation Constants ◽  
Aqueous Mixtures ◽  
Solvent Interactions ◽  
Gibbs Energies ◽  
Gibbs Energies Of Transfer ◽  
Solvent Systems

The thermodynamic first dissociation constants, [Formula: see text] of thymolsulfonephthalein (H2A), an uncharged acid, have been determined at 25 °C in aqueous mixtures of 10, 30, 50, 70, and 80 wt% acetonitrile (ACN), 11.52, 20.31, 29.64, and 36.83 wt% urea, 20, 40, 60, and 80 wt% dimethyl sulfoxide (DMSO) by spectrophotometric measurements. The solvent effect represented by ∂(ΔG0) = 2.303RT[p(sK)N − p(wK)N] is found to increase in ACN + H2O system as mol% ACN increases in the solvent. In contrast, the corresponding values in urea + H2O as well as DMSO + H2O solvent systems decrease with increase in proportion of organic component in the solvent, the decrease being sharp in urea + H2O. The results have been discussed in terms of the standard Gibbs energies of transfer of H+ from water to the mixed solvent, [Formula: see text] and the relative values of the standard Gibbs energies of transfer of HA−, [Formula: see text] and of [Formula: see text] in all the solvent systems. The overall dissociation behaviour of the acid (H2A) is found to be dictated by the specific solute-solvent interactions of the species participating in the dissociation equilibria.

Empirical polarity parameters for some binary solvent mixtures

1981 ◽  
Vol 34 (5) ◽  
pp. 933 ◽  
Author(s):  
S Balakrishnan ◽  
AJ Easteal
Keyword(s):  
Solvent Polarity ◽  
The Other ◽  
Binary Solvent ◽  
Solvent Mixtures ◽  
Additive Functions ◽  
Binary Solvent Systems ◽  
Solvent Systems ◽  
Highly Correlated ◽  
Ethanol Ethanol ◽  
Polarity Parameters

Values of the empirical solvent polarity parameters ET and Z have been determined as a function of composition for the binary solvent systems 1,2-dibromoethane + 1,2-dibromopropane, acetone + chloroform, acetone + ethanol, ethanol + chloroform and acetone + dichloromethane. For the 1,2-dibromoethane + 1,2-dibromopropane system both ET and Z are accurately linear (i.e. additive) functions of composition. For the other systems both parameters vary with composition in a strongly non-additive manner, and the deviations from additivity are interpreted in terms of intermolecular interactions. For these systems, in general ET and Z are not highly correlated, and neither parameter is highly correlated with other macroscopic properties or parameters derived from them.

Solvent Polarity Studies of the Water+t-Butyl Alcohol and Water+t-Butylamine Binary Systems With the Solvatochromic Dyes Nile Red and Pyridinium-N-phenoxide Betaine, Refractometry and Permittivity Measurements

1994 ◽  
Vol 47 (9) ◽  
pp. 1771 ◽  
Author(s):  
PK Kipkemboi ◽  
AJ Easteal
Keyword(s):  
Binary Systems ◽  
Hydrophobic Interactions ◽  
Nile Red ◽  
Solvent Polarity ◽  
Butyl Alcohol ◽  
Linear Functions ◽  
Non Linear ◽  
Organic Cosolvent ◽  
Two Parameters ◽  
Polarity Parameters

The empirical solvent polarity parameters ENR and ET for the solvatochromic compounds Nile Red (1) and pyridinium-N-phenoxide betaine (2), respectively, have been determined as a function of composition for water+t -butyl alcohol and water+t-butylamine binary mixtures, over the whole composition range at 298 K. For both systems the two parameters vary with composition in a strongly non-linear fashion, and the polarity of the mixture decreases with increasing proportion of the organic cosolvent. The non-linear variation of the polarity parameters is attributed to water-cosolvent hydrophobic interactions at low cosolvent contents, and hydrogen-bonding interactions at higher cosolvent contents. Permittivity and refractive index have also been measured at 298 K for both systems, and both properties are strongly non-linear functions of composition.

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