Acid-Base modern theory

Miskidjyan, S.P. Garnovskii, A.D. Introduction to the Modern Theory of Acids and Bases. Vysha Shkola Kiev, 1979. 

The early chapters in this book deal with chemical reactions. Stoichiometry is covered in Chapters 3 and 4, with special emphasis on reactions in aqueous solutions. The properties of gases are treated in Chapter 5, followed by coverage of gas phase equilibria in Chapter 6. Acid-base equilibria are covered in Chapter 7, and Chapter 8 deals with additional aqueous equilibria. Thermodynamics is covered in two chapters Chapter 9 deals with thermochemistry and the first law of thermodynamics Chapter 10 treats the topics associated with the second law of thermodynamics. The discussion of electrochemistry follows in Chapter 11. Atomic theory and quantum mechanics are covered in Chapter 12, followed by two chapters on chemical bonding and modern spectroscopy (Chapters 13 and 14). Chemical kinetics is discussed in Chapter 15, followed by coverage of solids and liquids in Chapter 16, and the physical properties of solutions in Chapter 17. A systematic treatment of the descriptive chemistry of the representative elements is given in Chapters 18 and 19, and of the transition metals in Chapter 20. Chapter 21 covers topics in nuclear chemistry and Chapter 22 provides an introduction to organic chemistry and to the most important biomolecules. 

Furthermore, it was necessary to remodel completely the remaining contents. First the theoretical portion had to be extended considerably. In all acid-base equilibria, activities and not concentrations determine the equilibrium conditions. Therefore, from a practical viewpoint, a summarizing description of the modern theory of strong electrolytes and of the activity concept is indispensable, especially since otherwise phenomena such as influence of dilution on the pH of a buffer mixture, or the salt vcrror of indicators, etc. have no quantitative explanation. 

This subject is too vast to cover even superficially, but it is worthwhile to show how the modern theory of heterogeneous catalysis is related to the topics in this book. " The key reaction is between the adsorbate molecule, acting as one reactant, and the surface atoms of the catalyst, acting as the second reactant. There is a transfer of electron density between the two reactants leading to chemisorption, and bond-breaking or weakening in the adsorbate. The acid-base character of the surface is matched to that of the adsorbate. ... 

The subject of salt effects in one which arises in all reaction-kinetic problems involving electrolytes and has no special relevance to acid-base catalysis. However, much of the early work on salt effects was in fact carried out with catalyzed reactions, and a neglect of these effects is still the commonest cause of misinterpretation of data on acid-base catalysis, so that a brief account will be given here. It is convenient to include under the heading of salt effects the various ways in which the assumptions of the classical theory have been modified by modern views on electrolytic solutions. Since the catalyst itself is commonly ionic, the same problems often arise even when no other electrolyte has been added to the system. 

The reagents are strong bases and poorly soluble metal hydroxides. In the above equations, the metal hydroxides function as acids, in agreement with the modern theory of their amphoteric behavior. As far as is presently known, the following metals (arranged in order of increasing valence) form hydroxo salts ... 

Modern advances in solvation theory are reviewed.A second critical review of the thermodynamic functions and crystallographic data of some solid solvates (e.g. NaI,3MeOH LiCl,py and CoCl2,6NHg) shows that the relative acid-base properties of the constituent cation, anion, and solvate molecule can well be described by the HSAB (hard and soft acids and bases) concept. ... 

In this chapter, we explain how the scientific understanding of acids and bases has changed through time. We start by explaining how to measure their strengths using the pH scale. We also explain the multiple theories of acid-base chemistry, from Lavoisier s first attempt to classify these materials, to the modern understanding of Lewis acids and bases. 

For example, little is known about acid-base interactions at solid/solid interfaces. It has long been recognized that molecular interactions across the interface between condensed phases may be split into physical and chemical terms. Physical interactions (vander Waals forces) contribute to the non-ideality of fluids and have been traditionally considered for interfaces. However, modern theories explain interfacial phenomena on solid surfaces, such as adhesion or wetting, in terms of chemical interactions. Moreover, the Lewis definition of acidity is so comprehensive that it can easily be accepted that most chemical interactions at solid surfaces may be effectively described as acid-base interactions [15]. continuously growing literature reinterprets interactions at solid/solid interfaces in terms of acid-base properties. For example, their role was shown in relation to solid/solid adhesion in film-substrate or fber-matrix systems as well as in wood and paper processing,... 

In the modern theory of surface science, Fowkes was the first to propose the theory of acid-base interfacial interaction [37 0]. 

The Arrhenius theory was the first modern acid-base theory developed. In this theory, an acid is a substance that, when dissolved in water, yields (Tiydro-gen) ions, and a base is a substance that, when dissolved in water, yields OH (hydroxide) ions. HCl(g) can be considered as a typical Arrhenius acid, because when this gas dissolves in water, it ionizes (forms ions) to give the ion. (Chapter 6 is where you need to go for the riveting details about ions.)... 

He wrote about 160 research papers, including those about the well-known theories for interfa-cial tensions discussed in this book, such as the earlier Good-Girifalco theory and the more modern acid-base theory of Card van Oss and M. K. Chaudhury. The first papers from these two theories have so far (2014) received about 1800 citations. 

Ideas about adds and bases (or alkalis) date back to ancient times. The word acid is derived from the Latin acidus (sour). Alkali (base) comes from the Arabic al-qali, referring to the ashes of certain plants from which alkaline substances can be extracted. The acid-base concept is a major theme in the history of chemistry. In this section, we emphasize the view proposed by Svante Arrhenius in 1884 but also introduce a more modern theory proposed in 1923 by Thomas Lowry and by Johannes Bronsted. 

The Arrhenius definition recognizes only OH as a base, but when we reconsider acids and bases in more detail in Chapter 16, we will see that modern theories identify and many other anions, including OH , as bases. 

The object of this book is to provide an introduction to electrochemistry in its present state of development. An attempt has been made to explain the fundamentals of the subject as it stands today, devoting little or no space to the consideration of theories and arguments that have been discarded or greatly modified. In this way it is hoped that the reader will acquire the modern point of view in electrochemistry without being burdened by much that is obsolete. In the opinion of the writer, there have been four developments in the past two decades that have had an important influence on electrochemistry. They are the activity concept, the interionic attraction theory, the proton-transfer theory of acids and bases, and the consideration of electrode reactions as rate processes. These ideas have been incorporated into the structure of the book, with consequent simplification and clarification in the treatment of many aspects of electrochemistry. 

The radical difference between the classical and modern views is readily seen from equations (17) and (18). The basic character, as defined by the older theory, actually is determined by the true acidic dissociation constant based on the hybrid ion conception. Conversely, the acidic nature is governed by the true basic dissociation constant. 

According to the modern version of the Arrhenius theory of acids and bases, a base is a substance that produces hydroxide ions, OH , when it is added to water. A solution that has a significant concentration of hydroxide ions is called a basic solution. Sodium hydroxide, NaOH, is the most common laboratory base. It is designated a strong base because for every NaOH unit dissolved, one hydroxide ion is formed in solution. 

According to the modern version of the Arrhenius theory of acids and bases, a base is a substance that produces when it is added to water. 

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