Thermodynamics Of Apolar Solvation In Mixed Aqueous Solvents
DOWNLOAD
Download Thermodynamics Of Apolar Solvation In Mixed Aqueous Solvents PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Thermodynamics Of Apolar Solvation In Mixed Aqueous Solvents book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Thermodynamics Of Apolar Solvation In Mixed Aqueous Solvents
DOWNLOAD
Author : Prateek Pinakin Shah
language : en
Publisher: ProQuest
Release Date : 2008
Thermodynamics Of Apolar Solvation In Mixed Aqueous Solvents written by Prateek Pinakin Shah and has been published by ProQuest this book supported file pdf, txt, epub, kindle and other format this book has been release on 2008 with Solvation categories.
Solubility of apolar molecules in aqueous media influences a number of natural and industrial processes. Examples range from the bioavailability of small-molecule pharmaceuticals to the fate of synthetic chemicals in the environment. Apolar solvation also plays a role in biological processes such as protein folding. Most theoretical investigations in the literature have focused on pure water as the solvent despite the fact that many natural and industrial systems include relatively high concentrations of cosolvents. Examples of common cosolvents include salts, alcohols, polyols, and carbohydrates. Despite the importance of mixed aqueous solvents, little work has been done to understand apolar solvation in these mixtures. Using molecular dynamics and statistical and classical thermodynamics, this thesis provides a systematic and extensive theoretical study of apolar solvation thermodynamics over a wide range of temperatures, pressures, and cosolvent compositions (up to 30 w/w% and 60 w/w% for the chosen cosolvents). The transfer free energy, enthalpy, and entropy of methane and hard sphere solutes are calculated in binary water-cosolvent (water-methanol, -ethanol, -sorbitol) mixtures, and a common molecular basis is shown to describe and predict the results across a broad range of solvent conditions. From a classical thermodynamics perspective, characteristic properties of water (i.e., temperature of maximum density and temperature of minimum solubility) are predicted by MD simulation to be suppressed to lower temperatures upon addition of either methanol or sorbitol as the cosolvent. This behavior holds across a wide range of temperature, pressure, and cosolvent concentration. By contrast, apolar solute solubility is increased by addition of methanol, but decreased by addition of sorbitol. These findings are in conflict with traditional classification schemes such as structure-making/-breaking and hydrophobic enhancement/suppression, and highlight the limitations of such heuristics for rationalizing cosolvent effects on solubility. Exact statistical mechanical theories of mixtures such as Kirkwood-Buff theory are also confirmed to be have limited predictive capability due to practical implementation issues that have been suggested previously in the literature. From a molecular perspective, it is shown that the distribution of void space is the dominant controlling factor that determines the sign and magnitude of the free energy of apolar solute dissolution in these water-cosolvent mixtures. This finding complements the literature for pure water and shows apolar solvation for small solutes is dominated by the work of cavity formation. Additionally, this thesis shows for the first time that the transfer free energy of apolar solutes from water to mixed aqueous solvents can be described by a common dependence on solvent packing fraction. This dependence is independent of temperature, pressure, and the cosolvent identity. The results also provide a clear molecular scale explanation for anomalous behaviors observed in simulation and experiment for apolar solvation in methanol-water mixtures; specifically, a minimum in apolar solute solubility is observed as a function of methanol concentration. Such solubility minima are shown to be due solely to the non-monotonic dependence of packing fraction on solvent composition (under isobaric conditions). This unusual behavior is due to competing effects between changes in the average molecular density and changes in the bulk density as solvent composition is changed at fixed temperature and pressure. This highlights that it is unnecessary to invoke arguments regarding alterations in hydrogen-bond network structures or the stability of hydrogen-bonded systems in order to explain any of these anomalous or characteristic solvation properties of water or mixed aqueous solvents. Rather, the attractive interactions between solvent molecules primarily determine the bulk density at a given temperature and pressure, and (small) apolar solute solubility is then determined by the efficiency with which solvent molecules pack (i.e., purely steric considerations) at that bulk density. Motivated by these findings, a thermodynamic cycle approach is proposed that separates the overall transfer process (at constant temperature and pressure) into two steps. The first step captures primarily the effects of changing solvent-solute interactions via changes in the solvent chemical composition. It occurs at fixed mass density to experimentally approximate fixed packing fraction. The second step is an expansion or compression of the binary cosolvent-water mixture to achieve the same pressure as the initial state point for the cycle. In such a manner, the effects of density changes with pressure (i.e., the equation of state, EoS) are quantified. Transfer free energies and enthalpies for methane across a range of solvents are captured qualitatively and semi-quantitatively using only the EoS step. The EoS step alone is able to quantitatively describe entropies of transfer; further emphasizing the dominant role of cavity formation and void distributions in apolar solvation across a range of solvents. Extension of this thermodynamic cycle approach to analyze protein unfolding is briefly presented, and illustrates a number of additional challenges for accurately capturing solvation thermodynamics of proteins in mixed aqueous solvents.
Solvation Thermodynamics
DOWNLOAD
Author : Arieh Y. Ben-Naim
language : en
Publisher: Springer Science & Business Media
Release Date : 2013-03-09
Solvation Thermodynamics written by Arieh Y. Ben-Naim and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-03-09 with Science categories.
This book deals with a subject that has been studied since the beginning of physical chemistry. Despite the thousands of articles and scores of books devoted to solvation thermodynamics, I feel that some fundamen tal and well-established concepts underlying the traditional approach to this subject are not satisfactory and need revision. The main reason for this need is that solvation thermodynamics has traditionally been treated in the context of classical (macroscopic) ther modynamics alone. However, solvation is inherently a molecular pro cess, dependent upon local rather than macroscopic properties of the system. Therefore, the starting point should be based on statistical mechanical methods. For many years it has been believed that certain thermodynamic quantities, such as the standard free energy (or enthalpy or entropy) of solution, may be used as measures of the corresponding functions of solvation of a given solute in a given solvent. I first challenged this notion in a paper published in 1978 based on analysis at the molecular level. During the past ten years, I have introduced several new quantities which, in my opinion, should replace the conventional measures of solvation thermodynamics. To avoid confusing the new quantities with those referred to conventionally in the literature as standard quantities of solvation, I called these "nonconventional," "generalized," and "local" standard quantities and attempted to point out the advantages of these new quantities over the conventional ones.
Thermodynamics Of Solvation
DOWNLOAD
Author : Gennadiĭ Alekseevich Krestov
language : en
Publisher: Prentice Hall
Release Date : 1991
Thermodynamics Of Solvation written by Gennadiĭ Alekseevich Krestov and has been published by Prentice Hall this book supported file pdf, txt, epub, kindle and other format this book has been release on 1991 with Science categories.
Aimed at scientists interested in the structure and dynamics of aqueous electrolyte solutions, this work examines the concept of the chemical nature of solutions. It shows quantitatively in tabulations of thermodynamic data for metal ions and anions the role of solvents as chemical reagents.
Single Ion Solvation
DOWNLOAD
Author : Philippe Hunenberger
language : en
Publisher: Royal Society of Chemistry
Release Date : 2015-10-20
Single Ion Solvation written by Philippe Hunenberger and has been published by Royal Society of Chemistry this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015-10-20 with Science categories.
Ions are ubiquitous in chemical, technological, ecological and biological processes. Characterizing their role in these processes in the first place requires the evaluation of the thermodynamic parameters associated with the solvation of a given ion. However, due to the constraint of electroneutrality, the involvement of surface effects and the ambiguous connection between microscopic and macroscopic descriptions, the determination of single-ion solvation properties via both experimental and theoretical approaches has turned out to be a very difficult and highly controversial problem. This unique book provides an up-to-date, compact and consistent account of the research field of single-ion solvation thermodynamics that has over one hundred years of history and still remains largely unsolved. By reviewing the various approaches employed to date, establishing the relevant connections between single-ion thermodynamics and electrochemistry, resolving conceptual ambiguities, and giving an exhaustive data compilation (in the context of alkali and halide hydration), this book provides a consistent synthesis, in depth understanding and clarification of a large and sometimes very confusing research field. The book is primarily aimed at researchers (professors, postgraduates, graduates, and industrial researchers) concerned with processes involving ionic solvation properties (these are ubiquitous, eg. in physical/organic/analytical chemistry, electrochemistry, biochemistry, pharmacology, geology, and ecology). Because of the concept definitions and data compilations it contains, it is also a useful reference book to have in a university library. Finally, it may be of general interest to anyone wanting to learn more about ions and solvation. Key features: - discusses both experimental and theoretical approaches, and establishes the connection between them - provides both an account of the past research (covering over one hundred years) and a discussion of current directions (in particular on the theoretical side) - involves a comprehensive reference list of over 2000 citations - employs a very consistent notation (including table of symbols and unambiguous definitions of all introduced quantities) - provides a discussion and clarification of ambiguous concepts (ie. concepts that have not been defined clearly, or have been defined differently by different authors, leading to confusion in past literature) - encompasses an exhaustive data compilation (in the restricted context of alkali and halide hydration), along with recommended values (after critical analysis of this literature data) - is illustrated by a number of synoptic colour figures, that will help the reader to grasp the connections between different concepts in one single picture
Thermodynamics Of Solutions
DOWNLOAD
Author : Eli Ruckenstein
language : en
Publisher: Springer Science & Business Media
Release Date : 2009-06-17
Thermodynamics Of Solutions written by Eli Ruckenstein and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2009-06-17 with Science categories.
This book consists of a number of papers regarding the thermodynamics and structure of multicomponent systems that we have published during the last decade. Even though they involve different topics and different systems, they have something in common which can be considered as the “signature” of the present book. First, these papers are concerned with “difficult” or very nonideal systems, i. e. systems with very strong interactions (e. g. , hyd- gen bonding) between components or systems with large differences in the partial molar v- umes of the components (e. g. , the aqueous solutions of proteins), or systems that are far from “normal” conditions (e. g. , critical or near-critical mixtures). Second, the conventional th- modynamic methods are not sufficient for the accurate treatment of these mixtures. Last but not least, these systems are of interest for the pharmaceutical, biomedical, and related ind- tries. In order to meet the thermodynamic challenges involved in these complex mixtures, we employed a variety of traditional methods but also new methods, such as the fluctuation t- ory of Kirkwood and Buff and ab initio quantum mechanical techniques. The Kirkwood-Buff (KB) theory is a rigorous formalism which is free of any of the - proximations usually used in the thermodynamic treatment of multicomponent systems. This theory appears to be very fruitful when applied to the above mentioned “difficult” systems.
Solvation Thermodynamics
DOWNLOAD
Author : Professor of Physical Chemistry Arieh Ben-Naim
language : en
Publisher: Springer
Release Date : 2014-01-15
Solvation Thermodynamics written by Professor of Physical Chemistry Arieh Ben-Naim and has been published by Springer this book supported file pdf, txt, epub, kindle and other format this book has been release on 2014-01-15 with categories.
Solvent Mixtures
DOWNLOAD
Author : Yitzhak Marcus
language : en
Publisher: CRC Press
Release Date : 2002-09-10
Solvent Mixtures written by Yitzhak Marcus and has been published by CRC Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2002-09-10 with Science categories.
Compiling, comparing, and analyzing research from a wide range of abstracts, journal articles, and Web sites, this reference examines the properties, function, and behavior of binary, ternary, and multicomponent mixtures in the presence and absence of solutes. The author uniformly presents extensive data on the properties of solvent mixtures and describes their structures and interactions. He details the impact of preferential solvation on the environment, action, and components of chemical systems. The book highlights experimental approaches to determine when, and to what extent, preferential solvation has taken place and models for organic, ionic, macromolecular, and biochemical solutes.
Thermodynamic Properties Of Nonelectrolyte Solutions
DOWNLOAD
Author : William Acree
language : en
Publisher: Academic Press
Release Date : 2012-12-02
Thermodynamic Properties Of Nonelectrolyte Solutions written by William Acree and has been published by Academic Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2012-12-02 with Science categories.
Thermodynamic Properties of Nonelectrolyte Solutions reviews several of the more classical theories on the thermodynamics of nonelectrolyte solutions. Basic thermodynamic principles are discussed, along with predictive methods and molecular thermodynamics. This book is comprised of 12 chapters; the first of which introduces the reader to mathematical relationships, such as concentration variables, homogeneous functions, Euler’s theorem, exact differentials, and method of least squares. The discussion then turns to partial molar quantities, ideal and nonideal solutions, and empirical expressions for predicting the thermodynamic properties of multicomponent mixtures from binary data. The chapters that follow explore binary and ternary mixtures containing only nonspecific interactions; the thermodynamic excess properties of liquid mixtures and ternary alcohol-hydrocarbon systems; and solubility behavior of nonelectrolytes. This book concludes with a chapter describing the use of gas-liquid chromatography in determining the activity coefficients of liquid mixtures and mixed virial coefficients of gaseous mixtures. This text is intended primarily for professional chemists and researchers, and is invaluable to students in chemistry or chemical engineering who have background in physical chemistry and classical thermodynamics.
Ion Solvation
DOWNLOAD
Author : Y. Marcus
language : en
Publisher: John Wiley & Sons
Release Date : 1985
Ion Solvation written by Y. Marcus and has been published by John Wiley & Sons this book supported file pdf, txt, epub, kindle and other format this book has been release on 1985 with Science categories.
Chemical reactions generally take place in solution and often involve ions. The behaviour of ions in solution, manifested through ion solvation, is therefore of prime interest in chemistry. This book considers in depth the phenomenology of ion solvation and the models and interpretations that have been proposed as the physical causes for the observed phenomena. It contains a thorough discussion of the statistical thermodynamic background of the solvation process from which a discussion of the actual thermodynamics is developed. This, in turn, serves as a background to the structural and kinetic features of ion solvation.
High Temperature Aqueous Solutions
DOWNLOAD
Author : Roberto Fernandez-Prini
language : en
Publisher: CRC Press
Release Date : 1991-12-19
High Temperature Aqueous Solutions written by Roberto Fernandez-Prini and has been published by CRC Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 1991-12-19 with Science categories.
This book provides a thorough discussion of the thermodynamics of aqueous solutions and presents tools for analyzing and solving scientific and practical problems arising in this area. It also presents methods that can be used to deal with ionic and nonionic aqueous solutions under sub- or supercritical conditions. Illustrations and tables give examples of procedures employed to predict thermodynamic quantities of the solutions, and an appendix summarizing statistical mechanical equations used to describe the systems is also provided. High-Temperature Aqueous Solutions: Thermodynamic Properties contains essential information for physical chemists, geochemists, geophysicists, chemical technicians, and scientists involved in electric power generation.