Thermodynamics of Ionization of Nitroethane in Water–Ethanol Solvent Mixtures

1974 ◽  
Vol 52 (10) ◽  
pp. 1910-1913 ◽  
Author(s):  
Takeki Matsui ◽  
Loren G. Hepler ◽  
Earl M. Woolley
Keyword(s):  
Mixed Solvent ◽  
Aqueous Ethanol ◽  
Equilibrium Constants ◽  
Glass Electrode ◽  
Solvent Mixtures ◽  
Calorimetric Measurements ◽  
Solvent Systems ◽  
Ionization Of Water ◽  
Thermodynamics Of Ionization ◽  
Acid Ionization

We have made glass electrode measurements that lead to values for the equilibrium constant for acid ionization of nitroethane in water and in aqueous ethanol mixed solvent systems. Calorimetric measurements have led to ΔH0 values for the acid ionization of nitroethane in water and in aqueous ethanol. These results have been combined to yield TΔS0 values for the ionization reactions in water and in aqueous ethanol. Our results have also been combined with previously reported equilibrium constants for ionization of water in aqueous ethanol to obtain thermodynamic data for the neutralization of nitroethane in the various solvent systems.

Aggregation studies of benzoporphyrin derivative

2001 ◽  
Vol 79 (5-6) ◽  
pp. 1068-1074 ◽  
Author(s):  
David Delmarre ◽  
Noboru Hioka ◽  
Ron Boch ◽  
Ethan Sternberg ◽  
David Dolphin
Keyword(s):  
Dielectric Constant ◽  
Photodynamic Therapy ◽  
Photophysical Properties ◽  
Equilibrium Constants ◽  
Solvent Mixtures ◽  
Ph Values ◽  
Beer's Law ◽  
Beer’S Law ◽  
Solvent Systems ◽  
Porphyrin Dimers

The photophysical properties of a ring B benzoporphyrin derivative 1,3-diene dimethylester were investigated in solution (water–DMSO mixtures). At low proportions of water in DMSO, the diester obeys Beer's law at all pH values and ionic strengths investigated. For solvent systems containing more than 30% water, the extent of deviation from Beer's law as a function of porphyrin concentration is attributed to formation of porphyrin dimers. Dimerization equilibrium constants (Kd) have been determined in different percentage of solvent mixtures, using absorption and fluorescence spectroscopies, and were found to exhibit a linear correlation between log (Kd) and the inverse of the dielectric constant (log (Kd) = 24.6 – 1060.4 × 1/εmix). This equation permits the calculation of Kd in mixtures of water–DMSO.Key words: porphyrins, dimerization, aggregation, fluorescence, benzoporphyrin derivative, photodynamic therapy, photosensitizers.

Thermodynamics of ionization of aqueous alkanolamines

1987 ◽  
Vol 65 (8) ◽  
pp. 1726-1728 ◽  
Author(s):  
Jin-Ho Kim ◽  
Celina Dobrogowska ◽  
Loren G. Hepler
Keyword(s):  
Aqueous Solution ◽  
Glass Electrode ◽  
Electrochemical Measurements ◽  
Calorimetric Measurements ◽  
Protonated Species ◽  
Thermodynamics Of Ionization

We have made electrochemical measurements with a glass electrode that have yielded pK values at T = 298.15 K for monothanolamine (MEA), triethanolamine (TEA), diisopropanolamine (DIPA), and methyldiethanolamine (MDEA) relative to the already well-known pK for diethanolamine (DEA), with all pK values referring to equilibria of the type AmH+(aq) = Am(aq) + H+(aq) in which Am(aq) represents an alkanolamine in aqueous solution and AmH+(aq) represents the corresponding protonated alkanolamine. We have also made calorimetric measurements leading to ΔH0 values for dissociation of the protonated species of all five of these alkanolamines in aqueous solution at T = 298.15 K. These pK and ΔH0 values have led to ΔG0 and ΔS0 values for the corresponding dissociation reactions of all five AmH+(aq) species.

scholarly journals Natural product mixture analysis by matrix-assisted DOSY using Brij surfactants in mixed solvents

RSC Advances ◽  
2014 ◽  
Vol 4 (79) ◽  
pp. 42029-42034 ◽  
Author(s):  
Mariano G. S. Vieira ◽  
Nilce V. Gramosa ◽  
Nágila M. P. S. Ricardo ◽  
Gareth A. Morris ◽  
Ralph W. Adams ◽  
...  
Keyword(s):  
Natural Product ◽  
Mixed Solvent ◽  
Mixed Solvents ◽  
Mixture Analysis ◽  
Surfactant Micelles ◽  
Product Mixture ◽  
Solvent Systems ◽  
Nmr Signals

Brij surfactant micelles in mixed solvent systems aid resolution of natural product NMR signals in diffusion-ordered spectroscopy.

scholarly journals A review on conductometric studies of electrolytes in mixed solvent systems to understand ion-ion and ion-solvent interactions

2020 ◽  
Vol 10 (3) ◽  
pp. 5355-5360
Keyword(s):  
Mixed Solvent ◽  
Mixed Solvents ◽  
Chemical Properties ◽  
Electrolyte Solutions ◽  
Molar Conductance ◽  
Extensive Literature ◽  
Solvent Interactions ◽  
Physico Chemical ◽  
Wide Range ◽  
Solvent Systems

The study of ion- solvent interaction is of much importance to investigate the nature of different solutions. Measurement of electrical conductivity and evaluation of physico-chemical properties, such as molar conductance, limiting molar conductance, ion-pair association, Walden product etc. shade light on different intermolecular interactions present in electrolyte solutions. Solvation properties can be varied by mixing two or more solvents. An extensive literature survey on conductometric studies has been carried out on different electrolytes dissolved in a wide range of mixed solvent systems. The reported results show that strong solute-solute, solute-solvent and solvent-solvent interactions are responsible for the physico- chemical behavior of a solution in mixed solvents.

Sign in / Sign up

Export Citation Format

Share Document