The Survival Guide For Physical Chemistry
Michelle M. Francl, Bryn Mawr College
To be published by Science Curriculum Press
Preface
The American Chemical Society sells a bumper sticker that reads "Honk if you Passed P-Chem" and while Iıve never actually seen it on a car, it certainly adorns bulletin boards and office doors in chemistry departments around the country. Physical chemistry is considered by many students to be the make or break course of the major. I certainly approached p-chem with trepidation, thanks in part to the stories my parents (both chemists) had to tell about their experiences. My mother boasts of climbing in the basement window of the p-chem lab at dawn to finish off an experiment - this in the days when women students had curfews. Forty years later, my father can still recite the physical chemistry problems on his graduate preliminary exams ("Water falls from a square faucet, what shape will it be when it hits the sink. Give all relevant equations."). Needless to say, by the time I was a junior chemistry major, physical chemistry had taken on mythical, and not very reassuring, proportions. Imagine my suprise when I found I enjoyed it - imagine my parentsı shock when I decided to pursue it as a career!
Part of the joy of physical chemistry for me is how many other parts of the field can be explored under its rubric. Physical chemists can explore organic, inorganic, and biological chemistry. Subjects as far afield as medicine, art and anthropology are also legitimate areas for the physical chemist to explore. Truly, physical chemistry can be fun! On the other hand, its breadth and its mathematical underpinings make it a challenge unlike any other chemistry course. This book is neither a math book nor a chemistry book. It tries instead to place the mathematics necessary for physical chemistry in a usable context. Itıs one thing to know the definition of a total derivative, itıs another to see how it can be used to derive the Maxwell relations in thermochemistry. Here are also collected many of the bits and pieces learned in earlier courses that can be frustrating and time-consuming to track down, such as the rules concerning rounding learned in general chemistry and the product rule for differentiation that is somewhere in the calculus text. Finally there is some advice that is useful I hope not only for surviving physical chemistry, but for making the most of it.
Most p-chem courses have a two or three semester calculus prerequisite. This certainly goes a long way to covering the math used in modern physical chemistry, but to round it out requires a smattering of other courses as well. Differential equations, linear algebra, probability and statistics, and computer programming courses would be a start. Not surprisingly, few students come with all these courses complete. Further difficulties ensue when the student discovers the knowledge gained in those courses doesnıt clearly transfer to physical chemistry. One of the major objectives of this book is to provide the student with a ready reference to the mathematical knowledge base assumed in a physical chemistry course and with ways to bridge the gap between the math and its application to the chemistry. The intent is not to replace the math courses, but to bring together in one spot most of the pieces that students need to be reminded of in a physical chemistry class. The basics are covered, such as how to integrate sin(x), as well as more sophisticated topics including numerical solutions to differential equations and operator algebra. Particular emphasis is put on techniques useful in physical chemistry that may not have been stressed in the corresponding math course, for example the use of a table of integrals.
Computers are a key element in the modern physical chemistry course. Their uses range from word processing to data acquisition. Students arrive in p-chem with varying levels of expertise, ranging from experienced system administrators and programmers to virtual novices (pun intended). This book aims to cover most of the usual uses in sufficient depth that a student could, using the appropriate manual, accomplish basic tasks. While the details of program use vary widely between applications, knowing that a task can be accomplished gives the student the incentive to figure out how. If you donıt know that you can set up a spreadsheet to do a repetitive series of calculations, you wonıt find out how. Topics covered include the use of symbolic math packages such as Mathematica and Maple, as these are coming into broad use.
Simply having the mathematical or computer skills is not enough for a student to be successful in p-chem. Students must also be able to problem-solve. Problems in physical chemistry tend to be complex and idiosyncratic, unlike the "plug and chug" problems that often make up the bulk of the problems encountered in general chemistry courses. Many students appear at my office door complaining "I donıt know how to start!" or "I didnıt get the answer in the back, but I canıt figure out whatıs wrong!" A major goal of this volume is to give students some techniques to deal with these difficulties, besides panic.
Writing is another common obstacle. Both the style and format expected in a science course differ substantially from that encountered in the humanities. Bibliographic materials are also dissimilar and students are sometimes intimidated. This book addresses common problems students have in writing for physical chemistry, for example, writing abstracts. It also provides a brief guide to the use of scientific library collections, including electronic materials. While students view writing skills as necessary for communicating their results, they often miss the boat when it comes to writing for the sake of documenting their lab work. Guidelines are given for the keeping of a laboratory notebook, including what to do when you write down the mass of the sample on that little slip of weighing paper instead of in your notebook.
The approach taken throughout this book emphasizes mechanics at the expense of theory. Examples of the techniques discussed are provided, along with heavily annotated solutions. The premise is that being able to reproduce an example is the first step to being sure one understands how to apply a technique. There are no problems to assign, this is meant to be a reference, not an additional text book. The techniques are meant to be applied to current problems, of which most physical chemistry students generally have a surfeit!
In writing this book Iıve aimed to give students a portable and readable collection of the information needed in physical chemistry. I also hope they have as much fun taking p-chem as I did twenty years ago, and still have teaching it!
Michelle M. Francl Bryn Mawr, PA June 2000Return to Michelle Francl's page.