In the Classroom: Writing
Writing Assignments in Physical Chemistry1 Lorrie Comeford Department of Chemistry and Physics, Salem State College, Salem, MA 01970 I have observed that many students approach physical chemistry as an exercise in flipping through the textbook to find the right equation. Although these students often calculate correct answers on exams, they do not understand the physical and chemical processes behind their answers. Teaching the quantum chemistry section of this course presents an additional challenge; I can not appeal to the student’s physical intuition. When I was introduced to writing to learn (1), I found a tool that helped me address this teaching challenge. Writing to learn has worked well in introductory classes (2–6), but has not been used as extensively in upper-level classes (7, 8).
Assignment 3 Read Chapters 7, 8 & 10 of the book. As you read, consider the following questions: •
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The Assignments Two problems had to be addressed before trying this kind of writing assignment: limited time and the need for an appropriate text on which to base the discussion. The book In Search of Schrödinger’s Cat: Quantum Physics and Reality, by John Gribbin (9), provided the basis for my writing assignments. This book traces the discovery of subatomic particles and atomic structure, outlines the failures of classical physics, and provides a nonmathematical overview of the interpretation of quantum mechanics. Written for the nonscientist, it is accessible to undergraduate students. The book was assigned in three parts, and students wrote a short (2–3 pages) essay as part of each assignment. To focus their writing, they were asked to respond to several questions. The assignments are shown below. The essays counted as homework assignments and were not assigned a letter grade. I commented on the content and responded to student questions. Assignment 1 Read Part 1 (Chapters 1–4) of the book. As you read, consider the following questions: • • • •
From your previous understanding of physics, are you surprised by the wave/particle duality of light? Has your understanding of the structure of the atom changed? Does this reading clarify any questions which you had after reading sections 10.1–10.4 of the textbook? What questions do you still have?
Assignment 2 Read Chapters 5 & 6 of the book. As you read, consider the following questions: • • •
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How does the description of electrons from General Chemistry compare to that presented here? What is your reaction to the first paragraph of the section entitled “A Break with the Past” (p 91)? How does this reading clarify any questions which you had about the Schrödinger equation after reading the textbook? What questions do you still have?
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How does our desire to make a model (wave/particle) hinder our understanding of quantum mechanics? What alternatives do we have to making a physical model? How do you suppose that concepts as important as those of quantum mechanics (Chapter 7) have escaped public notice? How does the interaction of observer and experiment in quantum experiments limit our ability to interpret the results of these experiments? Has your understanding of uncertainty changed? What questions do you still have?
Discussion Although I was frustrated by my students’ initial reluctance to try a new approach to learning this subject, I was struck by the difference these writing assignments made in our coverage of quantum chemistry. The students’ essays raised many thoughtful questions, and our subsequent class discussions were livelier, broader in scope, and more interesting than in previous years. The students were particularly interested in the controversy and passionate disagreement that surrounded the development of quantum theory. This type of paired reading/writing assignment could be used in almost any chemistry class where an outside text could expand the coverage of lecture material. Acknowledgment I am deeply grateful to Donnalee Rubin of the English Department at Salem State College for her help in composing the essay assignments and in preparing this manuscript. Note 1. This work was presented at the 13th Biennial Conference on Chemical Education.
Literature Cited 1. Connolly, P. In Writing To Learn Mathematics and Science; Connolly, P.; Villardi, T., Eds.; Teachers College: New York, 1989; Chapter 1. 2. Beall, H. J. Chem. Educ. 1993, 70, 10–11. 3. Beall, H.; Trimbur, J. J. Chem. Educ. 1993, 70, 478–479. 4. Cooper M. M. J. Chem. Educ. 1993, 70, 476–477. 5. Strauss, M. J.; Fulwiler, T. J. Coll. Sci. Teach. 1987, 16, 256–262. 6. VanOrden, N. J. Chem. Educ. 1990, 67, 583–584. 7. Wilson, J. W. J. Chem. Educ. 1994, 71, 1019–1020. 8. Combs, L. L. J. Chem. Educ. 1993, 70, 462–464. 9. Gribbin, J. In Search of Schrödinger’s Cat: Quantum Physics and Reality; Bantam: New York, 1984.
Journal of Chemical Education • Vol. 74 No. 4 April 1997
