Interactions solutés–solvants dans les mélanges eau – alcool tert-butylique. VIII. Volumes molaires apparents des benzoates halogéno-substitués

1977 ◽  
Vol 55 (22) ◽  
pp. 3866-3870 ◽  
Author(s):  
Nicole Dollet ◽  
Levon Avedikian ◽  
Jean Juillard
Keyword(s):  
Large Volume ◽  
Size Effects ◽  
Mixed Solvents ◽  
Butyl Alcohol ◽  
Benzoic Acids ◽  
Potassium Salts ◽  
Volume Changes ◽  
Tert Butyl Alcohol ◽  
Alcohol Mixtures ◽  
Molal Volumes

Apparent molal volumes of potassium salts of para-substituted (—F, —Cl, —I, —CH3) and unsubstituted benzoic acids in water – tert-butyl alcohol mixtures (0–40% by weight) are reported. Large volume changes are observed in media rich in water. Substituents size effects on both the location and the amplitude of the volume maxima are discussed in terms of the structure of the mixed solvents.

Thermodynamique de la solvatation d'acides protoniques et des bases conjuguées en milieux hydroorganiques riches en eau à 25 °C

1990 ◽  
Vol 68 (5) ◽  
pp. 655-665 ◽  
Author(s):  
Henri Gillet
Keyword(s):  
Butyl Alcohol ◽  
Enthalpies Of Formation ◽  
Organic Media ◽  
Enthalpies Of Solution ◽  
Potassium Salts ◽  
Enthalpies Of Transfer ◽  
Tert Butyl Alcohol ◽  
Organic Cosolvent ◽  
Alcohol Mixtures ◽  
Enthalpies Of Solvation

We have measured at 25 °C the enthalpies of solution of acetic, benzoic, and valeric acids and of their potassium salts in water – tert-butyl alcohol mixtures containing up to 40% by weight of organic cosolvent. We have also determined these quantities for phenol, aniline, and pyridine in the same mixtures and for acetic acid, aniline, and pyridine in water–DMSO, water–acetone, and water–urea in the zone rich in water. Using these data we have calculated the standard enthalpies of solution, the corresponding transfer quantities, and the enthalpies of solvation. When the enthalpies of solution are difficult or impossible to measure we have shown that the enthalpies of transfer can be calculated from judiciously selected transfer quantities obtained from experimental measurements. In this way we have worked out the enthalpies of transfer of potassium phenolate and of anilinium and pyridinium chlorides and bromides in the various mixtures. The enthalpies of solvation have been separated into enthalpies of formation of a cavity in the solvent and enthalpies of interaction. From these last quantities an attempt at interpretation in terms of solute and aqueous-organic media structures was made. Keywords: enthalpies, solution, solvation, acids–bases, aqueous-organic media.

Thermodynamic and Kinetic Investigation of the Solvent Effect on the Oxidation of [Co(en)2SCH2COO]+ with S2O82- In Water-Methanol and Water-tert-Butyl Alcohol Mixtures

1993 ◽  
Vol 58 (5) ◽  
pp. 1001-1006 ◽  
Author(s):  
Oľga Vollárová ◽  
Ján Benko
Keyword(s):  
Transfer Functions ◽  
Activation Parameters ◽  
Butyl Alcohol ◽  
Oxidation Of Co ◽  
Kinetics Of Oxidation ◽  
Tert Butyl ◽  
Tert Butyl Alcohol ◽  
Alcohol Mixtures ◽  
Kinetics Of

The kinetics of oxidation of [Co(en)2SCH2COO]+ with S2O82- was studied in water-methanol and water-tert-butyl alcohol mixtures. Changes in the reaction activation parameters ∆H≠ and ∆S≠ with varying concentration of the co-solvent depend on the kind of the latter, which points to a significant role of salvation effects. The solvation effect on the reaction is discussed based on a comparison of the transfer functions ∆Ht0, ∆St0 and ∆Gt0 for the initial and transition states with the changes in the activation parameters accompanying changes in the CO-solvent concentration. The transfer enthalpies of the reactant were obtained from calorimetric measurements.

Thermodynamic properties of aqueous organic solutes in relation to their structure. Part III. Apparent molal volumes and heat capacities of low molecular weight alcohols and polyols at 25 °C

1976 ◽  
Vol 54 (4) ◽  
pp. 624-631 ◽  
Author(s):  
Carmel Jolicoeur ◽  
Ghyslain Lacroix
Keyword(s):  
Butyl Alcohol ◽  
Heat Capacities ◽  
Apparent Molal Volume ◽  
Molal Volume ◽  
Specific Effects ◽  
Alkyl Groups ◽  
Tert Butyl Alcohol ◽  
Dilute Aqueous Solutions ◽  
Solute Interactions ◽  
Molal Volumes

The density and specific heat of dilute aqueous solutions of various alcohols and polyols have been measured at 25 °C. Such measurements have been carried out for the following solutes: methanol, ethanol, n-propanol, n-butanol, isobutanol, s-butanol, tert-butyl alcohol, n-pentanol. 3-pentanol, neo-pentanol, ethyleneglycol, 1,4-butanediol, 1,6-hexanediol, dimethyl-2,2-propanediol, 1,1,1-tris(hydroxymethyl)ethane, and pentaerythritol.The limiting apparent molal volume [Formula: see text] and heat capacities [Formula: see text] derived from these data exhibit some variations among the properties of isomers (e.g. branched vs. normal alkyl groups), but these variations cannot be conclusively attributed to specific effects in the hydration of the alkyl groups. On the other hand, the data allows one to derive group contributions to [Formula: see text] and [Formula: see text] namely [Formula: see text] for the methylene group, [Formula: see text] for the OH functional group and [Formula: see text] for the C—H of a terminal methyl group.The concentration dependence of [Formula: see text] brings out some interesting new features. With most of the alcohols, [Formula: see text] decreases with concentration, in a way related to the degree of hydrophobicity of the alcohol. Solute–solute interactions contribute to reduce [Formula: see text] of the hydrophilic solutes, but the opposite effect is observed with the most hydrophobic alcohols.

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