SolEq: Solution Equilibria, Principles and Applications finally came to life for me when I turned on the sound! I must admit I had been fumbling with the program for a while until the introductory audio clip (click "Sound On") pointed me in the right direction. Knowledge of the navigational flow is needed, but ideally, this program can replace many wet labs with superior quality electronic dry lab simulations.

Using eight computational packages, the program has 29 tutorials with simulations, calculations, and graphs, including 10 specifically for environmental chemistry and 2 for biological systems; the remaining are typical quantitative analysis exercises. These tutorials are also appropriate for industrial and coordination chemistry courses.

Three tutorials are used to teach the computational software packages Speciation, Acid/Base Titration, Titration City, and Metal/Ligand Titration. Actual instructions for using Speciation (sometimes referred to as "Species") and the Mini-SCDatabase are found on their respective program taskbars.

The 29 tutorials cover the theory and mathematics behind everything from stepwise and cumulative stability constants to pE and the Nernst equation. They generate speciation/pH diagrams, acid-base, metal-ligand, precipitation, and redox titration curves; perform buffer preparation and capacity calculations; and make equilibrium constant corrections for ionic strength and temperature using thermodynamic calculations. Simulations of changing concentration and pK_a values are possible through adjustment of slide bars found in the programs. Even the chelate effect, denticity, ring size, and macrocyclic effect are discussed. Specific examples found in the tutorials are modeling Cu²⁺, Zn²⁺, and Pb²⁺ in natural waters, modeling of major components in seawater, solubility of CO₂ in seawater, acid rain, and soil weathering.

The tutorials are interactive and provide real-life examples, which range from Lake Baringo, Kenya, to the Department of Energy Site K-25 at Oak Ridge, Tennessee. Pictures from around the world, as far south as the Antarctic and as far north as Sweden, and maps of the world with wind and deposition data are consistently found in hypertext-active links throughout all the tutorials. In some cases, the material is covered in considerably more detail than is available in current textbooks. Each tutorial begins with a list of learning objectives and ends with a summary and list of references, and can be printed in its entirety.

The tutorials increase in difficulty from Level 1 for freshmen and sophomores, to Level 2 for sophomores and juniors, to Level 3 for juniors and seniors. Each tutorial is structured as a series of tabbed "pages" that do not require any additional scrolling. Most pages have hypertext-active links to derivations of equations, constants, exercises, and worked answers. The tutorials can take 1 to 5 hours to complete if all the problems are attempted as each page is "turned". In some cases, an answer must be provided before continuing. In addition, a tool bar links the appropriate computational software needed to permit seamless movement from theory to problem solving.

Once the navigation is understood, it is easy to use the programs independently of the tutorials, and working files can be saved. The speciation graphs can be viewed linearly or logarithmically and changes to the numbers can be made to examine the effect. All the graphs and tables generated independently can also be printed.

However, in printing the graphs, the legend does not appear and the graph titles cannot be changed. Although scroll bars are not present, a few areas of text are cut off. In printed text, charges are missing from the chemical species. Toggling back and forth between linear and logarithmic graphs is not possible. These are the minor glitches in the programming. In addition, there is no instructor guide associated with the programming and the actual length of time that each tutorial should take is unknown. The tutorials have not been worked out in 3-hour slots for easy use in a laboratory setting.

SolEq teaches solution equilibria in an interactive tutorial fashion suitable for undergraduate lecture and laboratory use with applications in environmental, industrial, biological, speciation, and coordination chemistry. In addition, it can be used as an introduction to research in these areas. I highly recommend SolEq to be used as an educational tool and will probably use it in both the quantitative analytical chemistry and the environmental chemistry laboratory courses.