Solvent effect on the solution, ionization, and structure of aminosulfonic acids

1988 ◽  
Vol 66 (12) ◽  
pp. 3038-3043 ◽  
Author(s):  
Robert L. Benoit ◽  
Danielle Boulet ◽  
Monique Fréchette
Keyword(s):  
Solvent Effect ◽  
Thermodynamic Parameters ◽  
Enthalpies Of Solution ◽  
Ammonium Ions ◽  
Sulfonic Acids ◽  
Aliphatic Acids ◽  
Calorimetric Methods ◽  
Potentiometric And Calorimetric Methods

We have determined thermodynamic parameters for the solution and ionization in dimethylsulfoxide and water of four aminosulfonic acids: NH2(CH2)nSO3H with n = 0,1, and 2, and NH2C6H4SO3H. Potentiometric and calorimetric methods were used. The solubilities of the four acids in Me2SO are either nearly equal to or lower than in water, but the enthalpies of solution are 15–40 kJ mol−1 more exothermic in Me2SO. The three aliphatic acids are much weaker (2.1 ≤ ΔpKa ≤ 5.5) in Me2SO than in water and their heats of ionization are some 30 kJ mol−1 more endothermic in Me2SO. The discussion of our results is based on comparisons with corresponding data for related substituted amines and ammonium ions, and sulfonic acids and sulfonate ions. We conclude that the four aminosulfonic acids are mostly present as zwitterions in Me2SO just as in water.

Ionization of sulfonic acids and dimethylsulfoxide basicity. A 13C nuclear magnetic resonance and calorimetric study

1989 ◽  
Vol 67 (12) ◽  
pp. 2148-2152 ◽  
Author(s):  
Robert L. Benoit ◽  
Monique Fréchette ◽  
Danielle Boulet
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Bulk Water ◽  
Calorimetric Study ◽  
Enthalpies Of Solution ◽  
Sulfonic Acids ◽  
13C Nuclear Magnetic Resonance ◽  
Related Compounds ◽  
C Nmr ◽  
Nuclear Magnetic

The ionization of trifluoromethane-, methane-, and benzene-sulfonic acids in Me2SO and in water has been studied by 13C nuclear magnetic resonance. While the protonation shifts of CF3SO3− and CH3SO3− in both solvents are too small to make a quantitative interpretation possible, the C6H5SO3− shift data in H2O–H2SO4 mixtures, when treated by the method of Cox and Yates, gave a pKa value of −2.5 for the ionization of C6H5SO3H. Our results are discussed in relation to those of other workers. Enthalpies of solution and of ionization of these acids and related compounds have been obtained in both solvents. Single ion enthalpies of transfer from water to Me2SO have been calculated from our data and from a transfer value for CF3SO3− (+1.9 kJ mol−1) based on the tetraphenylarsonium–tetraphenylborate extrathermodynamic assumption. The transfers are endothermic processes for the anions CH3SO3− (+29.6 kJ mol−1), C6H5SO3− (+ 20.2 kJ mol−1), and p-CH3C6H4SO3− (+ 21.8 kJ mol−1), and exothermic for H+(−27.4 kJ mol−1). These results are discussed in terms of the properties of the ions and solvents. The transfer value for H+ is a valuable measure of the basicity difference between bulk water and Me2SO. Keywords: sulfonic acids, ionization, dimethylsulfoxide, 13C NMR, calorimetry.

Thermodynamic parameters for the basic ionization of some cyclic amines in water

1976 ◽  
Vol 54 (22) ◽  
pp. 3607-3613 ◽  
Author(s):  
Sheila Teresa Lobo ◽  
Tanikella S. S. R. Murty ◽  
Ross Elmore Robertson
Keyword(s):  
Thermodynamic Parameters ◽  
Dilution Method ◽  
Ammonium Ions ◽  
Cyclic Amines ◽  
Basic Dissociation ◽  
Acid Ionization

The thermodynamic parameters defining the basic dissociation in water of diethylamine, cyclohexylamine, piperidine, and quinuclidine have been determined by a dilution method based on conductance measurements. The values of ΔSa0 and ΔCpa0 for the acid ionization of the corresponding ammonium ions at 25 °C are ΔSa0 −8.08, −1.24, −8.51, −13.65 cal deg−1 mol−1 and ΔCpa0 13.9, −2.7, 18.0, 4.2 cal deg−1 mol−1. The relation between these derived values and solvation changes are discussed, the apparent anomalous values of ΔCpa0 for cyclohexylamine and quinuclidine being noted, but not rationalized.

Models of Thermodynamic Properties of Prominences

1979 ◽  
Vol 44 ◽  
pp. 349-355
Author(s):  
R.W. Milkey
Keyword(s):  
Thermodynamic Properties ◽  
Mass Transport ◽  
Emission Spectrum ◽  
Thermodynamic Parameters ◽  
Working Group ◽  
Physical Processes ◽  
Theoretical Concepts ◽  
Group 3 ◽  
Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

Solvent Effect on Optical Rotation I Optical Rotation ofl-Santonin

1960 ◽  
Vol 25 (1_2) ◽  
pp. 56-68 ◽  
Author(s):  
A. J. Mukhedkar
Keyword(s):  
Solvent Effect ◽  
Optical Rotation

ALDOSTERONE STIMULATION IN VITRO

1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller
Keyword(s):  
Ammonium Chloride ◽  
Human Urine ◽  
Incubation Medium ◽  
The Other ◽  
Ammonium Ions ◽  
Response Curves ◽  
Urine Extract ◽  
Similar Dose ◽  
Aldosterone Production

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.

Sorption of Heavy Metals by Bed Silts in the Presence of Ammonium Ions

2016 ◽  
Vol 38 (2) ◽  
pp. 96-100
Author(s):  
V. Shkapenko ◽  
V. Kadoshnikov ◽  
E. Musich ◽  
I. Pisanskaya
Keyword(s):  
Heavy Metals ◽  
Ammonium Ions
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