Aquatic chemistry deals with chemical reactions and processes affecting the distribution and circulation of chemical species in natural waters. This textbook/monograph focuses on physicochemical principles as they pertain to the identification of pertinent variables that determine the composition of natural aquatic systems. The student will discover that such basic processes as dissolution and precipitation, oxidations and reductions, and acid-base and complexation interactions in natural systems are very similar to those experienced in a chemical laboratory.

Following the 2nd edition published over twelve years ago, this text Aquatic Chemistry continues to emphasize the pedagogical approach from two fronts: (i) basic chemical principles in the quantitative treatment of the composition of natural waters, and (ii) the use of concepts of chemical equilibrium, rates of processes, and chemical reactions, to lay down the foundation for modeling natural systems. By comparison, this third edition is a greatly improved version due mostly to significant advances made during the last decade in the understanding of natural systems. In its teaching approach it employs general concepts and methods of problem solving so that the student may apply them to other aquatic systems. Every chapter has a bibliography of suggested readings and a list of relevant problems and answers. In addition, a hefty list of references (40 pages) is given at the end of the book along with various appendices of relevant tabulated thermodynamic data.

Several novel features are worth noting in this third edition. A new chapter (Chapter 5) has been added that treats interactions between the atmosphere and water; it also shows the interconnection between land, water, and air environments. For even though water is a minor component in the atmosphere, it nevertheless plays a significant role in chemical reactions in clouds, fog, and rain. In the treatment of solid/water interfaces, the authors have brought several major revisions. Surface chemistry is emphasized in the quantitative treatment of rate laws in geochemical processes (Chapter 13), whereas Chapter 14 shows how essential surface chemistry is for a proper interpretation of the behavior of colloidal systems in particle-particle interactions. The significant progress in concepts and experimental approaches made during the last few years is summarized in Chapter 9. For example, adsorption interactions of solutes with solid surfaces are characterized by (i) formation of surface complexes (chemisorption) and (ii) hydrophobic adsorption of nonpolar solutes to the solid surface. These two notions form the backbone for an understanding of the various processes in natural systems. In Chapter 6, treatment of metal ions and aqueous coordination chemistry have been updated to provide a greater understanding of metal ion speciation and complexation kinetics. Chapter 10 pays particular attention to the cycling and the biological role of trace metals in nutrition and in the toxicity of aquatic systems. Important advances in the understanding of mechanisms of redox processes are presented in Chapter 8, while novel interpretations of rates of electron transfer processes are considered in Chapter 11, and Chapter 12 presents photochemical principles and analyzes several important light-induced and photocatalyzed processes.

Pedagogically, this text is divided into two parts. The first part comprising chapters 2 through 9 represents a core of topics for an introductory course for advanced undergraduates and first-year graduates in environmental science and engineering, earth sciences, and oceanography, and would definitely be a relevant and rewarding elective course for chemistry majors. The second part comprising chapters 10 through 15 treats more advanced and detailed topics: (a) trace metals, (b) kinetics of redox processes, (c) photochemical processes, (d) kinetics at the solid/water interfaces, (e) particle-particle interactions, and (f) regulation of the chemical composition of natural waters.

It is relevant to examine the core chapters briefly. Subsequent to an introductory chapter (Chapter 1) on terminology and various fundamental constants, chapter 2 on Chemical Thermodynamics and Kinetics describes the principles and applications of two alternative models to treat natural waters: thermodynamic models and kinetic models. It is succeeded by a chapter on Acids and Bases, which depicts how interactions between acids and bases influence the composition of natural waters: it's been said that an ocean is the result of a gigantic acid-base titration. The distribution of CO₂, H₂CO₃, HCO₃^- and CO₃^2- in natural waters is considered in Chapter 4 (Dissolved Carbon Dioxide) together with an examination of CO₂ exchange between the atmosphere and the waters, with an evaluation of the buffering mechanisms of fresh waters and seawater, and with a definition of their capacities for acid and base neutralization. In Chapter 5, some important reactions at the gas/water interface are described and the partitioning of molecules between the gas phase and the aqueous phase (Henry's law) is discussed extensively. The chapter also treats processes that affect wet and dry deposition and the composition of atmospheric water droplets (clouds, fog, rain, snow, dew) and illustrates how pollutants released into the atmosphere are transferred back to the soil. Chapter 6 entertains several aspects of coordination chemistry and metal ions in aqueous solutions, while Chapter 7 (Precipitation and Dissolution) sets forth principles that concern reactions between solids and water utilizing equilibrium relations. Chapter 8 on redox equilibria and microbial mediation stresses the stability relations of pertinent redox components in natural water systems. Chapter 9, the last chapter in the core program, deals with solid/solution interfaces. It emphasizes the action of water on minerals that produce very high surface areas and reactive and with catalytic materials in surface environments.

This book on Aquatic Chemistry is highly recommended for course adoption for a 1- to 2-semester course in fields dealing with natural water environments. Students and seasoned workers interested in natural aquatic environments and, by extrapolation, in the detoxification of environmental pollution will find this text/monograph an excellent companion to an earlier one, Environmental Organic Chemistry (Wiley-Interscience; 1993; ISBN 0-47-83941-8), and a good addition to one's personal library.