The thermodynamic properties of solutions of normal and branched alcohols in benzene and n-hexane

A comparative study of thermodynamic properties and molecular interactions in mono- and polychloroalkane + n-alkane or + cyclohexane mixtures

Interactions diastereoisomeres d'antipodes en phase liquide

A survey is made of the enthalpies of formation, third law entropies and Gibbs energies available for Krebs cycle and related compounds. These include formate, acetate, succinate, fumarate, glycine, alanine, aspartate and glutamate. The potential of the NAD+/NADH couple is recalculated based on the ethanol/acetaldehyde and isopropanol/acetone equilibria. The reported enzyme catalyzed equilibrium constants of the Krebs cycle reactions are evaluated with estimated errors. These 28 equilibria form a network of reactions that is solved by a least squares regression procedure giving Gibbs energies of formation for 21 Krebs cycle and related compounds. They appear to be accurate to ±0.4 kJ⋅mol−1 for some compounds but ±1 kJ⋅mol−1 in less favorable cases. This procedure indicates which third law ΔfG and enzyme equilibria are inaccurate, and allows very accurate ΔfG to be determined for compounds related to the Krebs cycle by measuring enzyme equilibrium constants.

The Thermodynamics of the Krebs Cycle and Related Compounds

Calorimetric measurements of the heat of mixing have been made at 25.0±0.01°C for binary mixtures of n-butanol with polar liquids (acetonitrile, acetone, n-butyl ether, and n-butyl amine), and for binary mixtures of polar liquids with n-hexane. The calorimeter for measuring the heats of mixing was of twin type, and a thermomodule, HTM 0516 type (Sharp Electric Co., Ltd., Osaka) was used as the temperature-sensing device. By plotting the values of the heat of mixing, ΔHx1M, against the mole fraction of component 1, x1, and by extrapolating the curve to an infinite dilution (x1→0) for each system, the heats of mixing per mole of component 1 at an infinite dilution (\undersetx1→0limΔHx1M) were obtained graphically. By using the values of \undersetx1→0limΔHx1M obtained for these systems and by using the same treatment as that described in a previous paper [S. Murakami, K. Amaya and R. Fujishiro, This Bulltein, 37, 1776(1964)], the intermolecular hydrogen bond energies between alcohol and polar molecules were ...

The Heats of Mixing for Binary Mixtures. III. The Intermolecular Energy of Hydrogen Bonding between Alcohol and Several Other Polar Molecules

A microcalorimeter of the twin type has been constructed, one which is operated semiautomatically. Using this apparatus, the heats of mixing for alcohol-ketone, alcohol-hexane, and ketone-hexane solutions have been measured. From these heats of mixing, the hydrogen bond energy of the O–H…O= type has been estimated to be about 4kcal. by means of the thermochemical cycle.

Heats of Mixing for Binary Mixtures. The Energy of Hydrogen Bonding between Alcohol and Ketone Molecules

The heats of mixing were measured for 22 binary systems of polar and non-polar liquids where the pairs of liquids have similar molecular sizes. For the systems in which the non-polar components are non-aromatic, the van Laar coefficients α are positive and increase smoothly as the concentration of polar liquids decrease. This variation of α with concentration is attributed to the effect of dipole of the polar component. However, for the systems where the nonpolar components are aromatic, the values of α are smaller than that of the corresponding non-aromatic system and are even negative for most of the cases and decrease with concentration of polar component in most concentration ranges. The sharp difference between two groups of the binary systems, was attributed to the structural difference of aromatic and non-aromatic non-polar components. The effect presumably due to the quadrupole of the non-polar components was noticed.

Thermodynamical Studies on Binary Systems Consisting of Polar and Non-polar Liquids. II. The Measurement of the Heats of Mixing for Binary Systems of Polar and Non-polar Liquids

The statistical mechanical expression relating the solubilities of d- and l-optical isomers in optically active solvent is derived. It is shown that there exists a difference between these two solubilities. The possibility of optical resolution is also discussed.

Statistical Thermodynamics of Solutions of Optically Active Substances. II. Solubility of d- and l-Isomers in Optically Active Solvents

Heats of mixing of optical isomers in solution: calorimetric evidence of stereospecific effect

The heats of dilution in the systems of polystyrene - benzene and polystyrene-cyclohexane were measured and the values of interaction parameters were derived. The heat of mixing of ethylbenzene, which may be regarded as the monomer unit of polystyrene, with the same solvents was also measured and it was found that the interaction of polymer solutions has the same sign as those of the corresponding monomer unit solutions.

Kazuo Amaya

Papers

Heats of Mixing for Binary Mixtures. The Energy of Hydrogen Bonding between Alcohol and Ketone Molecules

Thermodynamical Studies on Binary Systems Consisting of Polar and Non-polar Liquids. II. The Measurement of the Heats of Mixing for Binary Systems of Polar and Non-polar Liquids

Statistical Thermodynamics of Solutions of Optically Active Substances. II. Solubility of d- and l-Isomers in Optically Active Solvents

Heats of mixing of optical isomers in solution: calorimetric evidence of stereospecific effect

Heats of Dilution of Polystyrene Solutions. II