In the Classroom
Writing in Chemistry: An Effective Learning Tool Jeffrey Kovac* Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600;
[email protected] Donna W. Sherwood Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996-2010
A major challenge facing chemical education is the diversity of student backgrounds, abilities, and interests, particularly in the introductory courses. To accommodate this diversity, chemistry faculty have begun developing a variety of pedagogical techniques to provide entry points for students and to facilitate active learning and critical thinking (1). One of the most powerful techniques is perhaps the oldest: writing. Productive scholars have always known that “writing is thinking”; ideas are usually best developed and clarified on paper or, today, at a keyboard (2). In fact, the teaching of writing can help chemistry faculty to meet important teaching challenges. The insight that writing is an effective learning tool gave rise some two decades ago to the writing across the curriculum movement, which has produced a large body of literature (3) including a number of previous articles in this Journal and other journals devoted to science education (4 ). This rich tradition has informed our work by providing both a philosophical underpinning and a large number of specific and practical ideas. The challenges in teaching large, diverse classes include (i) providing entry points to the subject for students with varied interests and learning styles; (ii) helping students develop a conceptual understanding of the course material; (iii) developing learning and professional skills; (iv) reintegrating student knowledge by connecting chemistry to a student’s proposed major and to the broader liberal arts (5); and (v) providing enrichment opportunities for interested students. Most of these challenges are poorly addressed by the lectures, discussions, laboratories, and problem sets of the usual chemistry course. Faculty may naively have assumed that if students can solve the numerical problems integral to a first-year chemistry course, they thoroughly understand the concepts that underlie those problems. Recent research into student learning, however, shows that this assumption is probably incorrect (6 ). In an increasingly crowded curriculum it is difficult to make strong connections to all the possible majors represented in a large class or to lend a broad historical, cultural, and philosophical perspective to the subject matter. Since chemistry is content-rich, it is easy to cover the material but neglect the development of such intellectual process skills as reading, critical thinking, and problem solving. But content and process are synergistic, and both must be developed systematically if students are to become independent learners (7 ). If chemistry faculty use writing assignments to promote independent learning, they will also address students’ future professional needs. One major complaint from industry and from graduate programs is that students graduating with degrees in chemistry—and other fields—do not write effectively. While most college students must pass an English composition course or its equivalent, few chemistry and other science stu-
dents get substantive training or practice in the professional writing tasks they will face when they go to work. Many students leave college without learning the style and conventions of scientific and technical communication. Some chemistry majors may never even have seen The ACS Style Guide (8). Writing, then, has complementary functions in education and the professions. First, it is a powerful learning tool. The best way to clarify thinking is to put early thoughts on paper for someone else to read. Second, writing is an essential professional skill. Consequently, it seems logical that writing should be an important component of education in chemistry–and for that matter, in any discipline. Chemistry faculty interested in translating this insight into practical pedagogy encounter two major barriers. The first is assignment design: how and where to use writing in an individual course or across the entire chemistry curriculum. The second is grading: how to evaluate student writing efficiently and offer responses that help students improve both writing and critical thinking skills. For the past few years we have been developing a systematic approach to using writing as an effective learning tool in chemistry courses and testing this approach in high-enrollment general chemistry courses at the University of Tennessee, Knoxville. Our experiences have suggested some general strategies for using writing in chemistry courses. More details can be found in our recently completed Writing Across the Chemistry Curriculum: A Faculty Handbook (9). Writing in General Chemistry For several years one of us (JK) has assigned writing in high-enrollment sections of general chemistry. Because students were not grasping larger concepts through solving numerical problems, he chose writing as one good way to help them deepen their conceptual understanding. Because time constraints preclude reading and grading traditional term papers in high-enrollment courses, microthemes, one-page essays on focused topics, were used instead (10). A carefully constructed microtheme assignment prompts students to think carefully and write creatively about a chemistry topic and keeps the grading demands manageable. With holistic grading, a single comprehensive reading of the paper focused on total impact, 125 microthemes could be evaluated in about four hours. In larger sections, simple, reliable systems can be used to train teaching assistants to grade holistically. During spring semester 1997 JK made four microtheme assignments in his section of a first-semester mainstream general chemistry course at the University of Tennessee, Knoxville (Chemistry 120). This fairly traditional course is based on Darrell Ebbing’s textbook, General Chemistry (11). The 125 students enrolled in the section met twice a week for lectures, once a week for a discussion led by a
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In the Classroom Table 1. Writing Assignments for Spring 1997 No. Writing Assignment 1
In a coherent one-page essay list the postulates of Dalton’s original atomic theory and discuss how subsequent discoveries have caused these postulates to be modified. Have the modifications of the postulates altered the essential content of the theory?
2
In a coherent one-page essay clearly define the three types of chemical reactions discussed in chapter 3 of Ebbing: precipitation, acid–base, and oxidation–reduction. What are the essential characteristics of each type? Where appropriate you should list the similarities and differences between the different classes of reactions.
3
In a coherent one-page essay clearly describe how you can use combustion analysis and gas density to determine the molecular formula of an organic compound consisting only of carbon, hydrogen, and oxygen. As part of your paper you should briefly describe the experiments that must be performed, but concentrate on the analysis of the data. Be sure to list the assumptions that are made in the analysis of the data. Use mathematical equations where appropriate, but make sure that you have described the procedures clearly in words.
4
One of the characteristic features of atoms is that their emission spectra are discontinuous line spectra rather than the continuous spectrum of sunlight. The physical origin of this remarkable observation was first explained in detail by Niels Bohr. In a coherent one-page essay summarize the Bohr theory and show how it explains the emission spectrum of the hydrogen atom.
teaching assistant, and once a week for a three-hour laboratory. Writing was one of a variety of cooperative and active learning techniques for the course (12). The four writing assignments were spaced evenly through the 14-week semester, roughly three weeks apart. Students had one week to complete each assignment. Each topic was chosen to stimulate thinking about an important idea in the course and to develop conceptual understanding. JK graded all four assignments (see Table 1) holistically on a scale of 1 (low) to 6 (high), making no comments on the papers. He posted the best papers from each set, with names removed, on the course bulletin board. At the end of the semester, holistic scores from the first two writing assignments were summed, converted to a 100-point scale, and recorded as a single writing grade. Scores from assignments three and four were treated in the same way. The two writing grades, representing the four assignments, accounted for about 7% of the course grade. When students evaluated the various pedagogical techniques used, including the writing assignments, their reaction to the writing was quite negative. Numerical ratings were low, and the free responses contained such comments as “worthless” and “busy work.” While no causal conclusions can be drawn from these data, a numerical correlation between course grade and writing assignment grade (see Table 2) indicates a strong connection between writing quality and the student’s success in the course. Clearly the writing assignments might have been used more effectively. First, students did not understand the holistic grading; they expected Table 2. Correlation of Course comments and correcGrade with Writing Grades in tions. While posting Chemistry 120, Spring 1997 the best papers Writing Grade for Course seemed a good way to Assignments Letter No. provide a learning Grade 1 and 2 3 and 4 model, the students A 24 80.0 73.3 needed clearer success B+ 4 72.5 67.5 criteria. Second, stuB 26 72.1 62.8 dents felt four papers were too many and alC+ 5 64.0 60.0 lowed them too little C 40 66.4 50.1 time to do their best D 24 63.1 59.3 work. Finally, the conF 39 48.2 19.4 nection between writing 1400
and the rest of the course could have been better clarified by calling for well-written essay answers on exams. In fall semester 1997 JK taught a 400-student section of Chemistry 120 and again used writing assignments, this time assigning only two microthemes (see below) and giving students two weeks to complete each assignment. Student response was no better. Even though the revised assignment sheets contained more detailed expectations and success criteria, students still felt they needed more information. Short essay questions on the examinations showed the importance of writing, but students still made little connection between writing and learning. Writing Assignments for Fall 1997 GUIDELINES FOR WRITING ASSIGNMENTS Your papers should be confined to no more than one doublespaced typewritten page (about 250 words). Neatly handwritten papers are also acceptable, but they should also be confined to one page. If you do not know how to use a word processor, now is a good time to learn. Do not put your paper in a binder or folder. Do not use a cover page. Make sure that your name, section number and the name of your teaching assistant are on the top of the page. Submit only ONE PAGE. Papers are due at lecture on the date specified. Late papers will only be accepted with independent written confirmation of an acceptable excuse (illness, family emergency, or universitysponsored activity). Failure to turn in a paper will result in a severe grade penalty. A holistic grading system will be used. Both content and form are important. Your paper should be scientifically sensible and well written. Well written refers both to mechanics (grammar, punctuation, spelling, etc.) and to good construction (organization, clarity, style, etc.) Papers will be graded on a scale of 1 (low) to 6 (high). For a paper to receive a grade of 4, 5, or 6 it must have good content and be well written. Major deficiencies in either content or construction will result in a grade of 1, 2, or 3. Because of the number of students in the class it will not be possible to make detailed comments on each paper. The readers will note editorial glitches, places where the writing is unclear due to grammatical or organizational problems or poor writing. Examples of excellent papers will be posted on the bulletin board (with the names removed) to give you an idea of what is expected. If you have questions about the grading of your paper or need suggestions on how to improve, please see Dr. Kovac. Each writing assignment is equal to one quiz grade. The two writing grades will be summed and converted to a 100-point scale as follows: 6 = 100, 5 = 90, 4 = 80, 3 = 70, 2 = 60,
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In the Classroom 1 = 50. If the paper is not turned in, the grade will be 0. WRITING ASSIGNMENT #1 In a coherent one-page essay discuss how a balanced chemical equation exemplifies the postulates of Dalton’s original atomic theory. WRITING ASSIGNMENT #2 In a coherent one-page essay clearly describe how you can use combustion analysis and gas density to determine the molecular formula of an organic compound consisting only of carbon, hydrogen, and oxygen. As part of your paper you should briefly describe the experiments that must be performed, but the focus of your essay should be the analysis of the data. Be sure to list the assumptions that are made in the analysis. Use mathematical equations where appropriate, but make sure that you have described the procedures clearly in words.
Obviously, negative student comments about writing assignments are common, even in writing emphasis courses. Often those student complaints excuse the students’ own limitations. In many circumstances efforts to expand a student’s intellectual and personal horizon are met with resistance and even anger (13). JK, as lecturer, holistically graded the first set of 400 papers—a virtually impossible task. For the second set he taught his teaching assistants (TAs) a simple and effective system for holistic grading. JK read a representative sample of the papers and selected two or three as “benchmarks” for each score on the 1-to-6 scale. The TAs used the benchmarks for evaluating the papers in their own sections. Before marking scores, the TAs passed their papers on for independent evaluation by a second TA. If the two scores were within one point of each other, the student received the higher grade. When the scores differed by more than one point, the lecturer assigned the final grade. A spot check of TA grades showed them to be reasonably consistent with lecturer’s scores. Another possibility is to have students exchange papers for peer assessment, which can be a powerful means to provide feedback in courses that do not have adequate TA support. The students would need guidelines for their assessments and, ideally, a set of benchmark example papers. If benchmark papers are provided they should not only have the names removed but should come from a previous class to preserve confidentiality. JK also addressed student reading skills in this course. Chemistry faculty have observed informally that students in first-year (and higher) courses cannot read the textbook efficiently and effectively; often they take no notes and highlight everything. JK tried an informal writing assignment: the reading notebook. Given written general guidelines for reading a science textbook and specific study questions for each chapter, students were asked to keep a reading notebook with written notes and answers to the study questions (see sample assignment below). The notebooks were holistically evaluated at semester’s end and counted as about 4% of the course grade. Sample Reading Notebook Assignment READING NOTEBOOK ASSIGNMENT—CHAPTER 1 General methodology for reading a chemistry textbook 1. Quickly scan the whole chapter to get a general idea of what it contains. In your notebook write a brief outline of the chapter material. 2. In your notebook briefly state the purpose of reading the material. The statement of purpose should be specific. “To pass Chemistry 120” is not acceptable.
3. As you read, identify the new terms that are introduced in the chapter. In your notebook make a list of the new words and terms, both scientific and non-scientific. Use the glossary and a dictionary to write out clear definitions of the new terms. While this list of new terms will depend on your personal background and vocabulary, Dr. Kovac will be very skeptical of a reading notebook that has no new terms. 4. As you read the chapter, identify the prerequisite knowledge, either from earlier chapters or from previous courses in science or mathematics, needed to understand the material in the chapter. In your notebook, briefly describe the prerequisite knowledge. If you feel comfortable with your understanding of the prerequisites, you do not need to do any more. If not, you should review the prerequisite knowledge in earlier chapters or in appropriate references. In your notebook write a brief summary of what you reviewed. 5. As you read, make notes and observations about the key points made in the chapter. The specific questions below will guide your reading. Answers to the specific questions must appear in your notebook. 6. After you finish reading, write answers to the following general questions about the chapter: (1) How will you integrate the information in this chapter with what you have learned previously in this course and in other courses? (2) How does the information in this chapter relate to your major or projected career? What will you be able to use in the future? (3) What questions do you still have about the information presented in the chapter? (4) What insights do you have that you would like to share with other students? SPECIFIC QUESTIONS FOR CHAPTER 1 These questions should be answered in complete sentences. A yes or no answer is not sufficient. 1. What is meant by the precision of a measurement? How is the precision indicated? What is the difference between precision and accuracy? 2. What are the ethical implications of reporting a number to a greater precision than it has been measured? 3. Give three examples of each of the following: pure substance, homogeneous mixture, and heterogeneous mixture. What are the essential characteristics that distinguish the three kinds of substances? 4. Describe, in words, the factor-unit method of problem solving. What is the advantage of using this method? Does the method clearly illustrate the logic used to solve problems, or should you provide other information to document your solution to a problem? 5. Give three examples of chemical and physical processes. What are the essential characteristic that distinguish the two kinds of processes? 6. How can you distinguish between a compound and an element? 7. Clearly define the density of a substance. Why is density a useful characteristic property? Think of a real-life situation in which you would use density to distinguish between two similar substances.
Student response to the reading notebook was mixed. Roughly 25% agreed that the notebook was valuable and 45% disagreed. The remaining 20% were neutral. While some students found the reading notebook helpful, others saw it as busy work. Others felt that the reading notebook percentage of the grade was too small for the amount of work required. In retrospect, the major problem with the reading notebook was its loose integration into the course. To help students see the value of their work more immediately and directly one could allow an open reading notebook for quizzes or even exams. Also, more credit could be assigned, and early assessment and feedback opportunities could be given. Significantly,
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In the Classroom
however, students who seriously undertook the reading notebook assignment claimed that they learned how to read and understand a textbook and to take focused reading notes, a useful skill for any profession. These experiments were part of a broader effort to develop a systematic approach to using writing as an active learning tool in chemical education. We have tried to integrate chemistry professors’ best experiences using writing in their courses with the rhetoric and composition literature and the writing across the curriculum movement. Our practical guide offers chemistry (and other science) faculty interested in this technique ways to overcome the common barriers: assignment design, strategy, and, finally, assessment and grading. If writing is taught across the entire chemistry curriculum and department-wide criteria can be established, student appreciation of writing to learn can be expanded. Writing Across the Chemistry Curriculum Students and faculty look at a writing assignment with quite different eyes. Even experienced faculty underestimate student difficulty with the usual writing topic. Too often, in fact, unstated criteria are present, assumptions about the nature of the audience and the assessment standards. The intellectual and rhetorical tasks may require more sophistication than most students possess. Students may not understand the relevance of the assignment to course objectives. Faculty may blame students for poor writing when the assignment is at least as much a culprit. Even if the assignment works well, chemistry faculty, generally not trained to teach writing, may falter at the prospect of evaluating student papers and giving useful feedback to help students improve their writing skills. While much is known about designing effective writing assignments and their systematic use for developing thinking and rhetorical skills, this information is found mainly in the composition and rhetoric literature and in a context and style unfamiliar, and sometimes forbidding, to chemists. One major goal of our handbook is to offer practical advice to chemistry faculty for designing and grading writing assignments. To aid in matching the intellectual and rhetorical tasks to student abilities, we have adopted an eight-level hierarchy, similar to Bloom’s taxonomy, introduced into the composition literature by Kiniry and Strenski (14 ) and adapted for Table 3. Writing Task Hierarchy No.
Task
Description
1
Listing
Display of important items
2
Definition
Brief or extensive explanation of a word or concept
3
Seriation
Ordered list or description of a procedure
4
Classification
Application of specific categories to specific data
5
Summary
Identification of important facts and ideas in a reading
6
Comparison/Contrast
Listing/analysis of similarities and differences
7
Analysis
Breaking down a complex idea into its constituent parts
8
Academic/Scientific Argument
Use of facts and theories to support a proposition
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chemical education by Rosenthal (15). This hierarchy (Table 3) begins with easy tasks like listing and definition and ends with academic or scientific arguments likely to require all the intellectual tools developed at lower levels. The hierarchy serves two purposes: first, it helps an instructor understand the intellectual and rhetorical demands an assignment makes on students; second, it facilitates systematic development of intellectual and writing skills in a course or across a curriculum. Other important considerations in assignment design are the topic type, audience, and rhetorical form. Another factor is writing context, which has three components—writer, subject, and audience. Generally one of the three context considerations is emphasized. In explanatory writing, the subject is most important; when persuasion is the goal, audience moves to the fore; and in expressive writing, the writer is closer to the center of awareness. Because both explanatory and persuasive writing are important in science, students need to know the difference between them and how each can incorporate the other. Expressive writing is seldom used professionally, but it can be quite effective as a writing-to-learn tool; journals, for example, in which students record and think about their own understanding of chemical concepts, can be effective learning tools. Whatever the particular assignment, models of successful writing, either published or from previous classes, will be helpful. One major potential problem for writing assignments in science is a failure to specify the audience. If students do not understand for whom they are writing, they become increasingly confused about which of their own writing voices to use. In the absence of clear instruction, they will write for you—or worse, what they imagine you to be. Scientists usually write for three types of audiences: experts, scientifically educated nonexperts, and general readers. An article for The Journal of the American Chemical Society is quite different from one for Discover or The New York Times. A clear definition of audience is essential to any writing assignment. As for rhetorical form, scientists use many forms, and students should be exposed to those that will be important in their professional careers. Clearly students must know the form for the paper they are to write as well as details such as the number of words or pages, margins, and font size. Finally, the writing process itself must be outlined. Will a first draft be required? Is the instructor available to review intermediate drafts? Will there be a peer-review process? These questions must be answered in the assignment. All these factors in the assignment should be tailored to any of the many possible course objectives you wish to address through writing assignments. As we said at the beginning, the objectives include conceptual understanding, skill development, reintegration of knowledge, and enrichment. Using the advice above, faculty can prompt students to deeper and broader learning in any course. After the papers have been written, they must be assessed or evaluated. Again, grading is time consuming and sometimes dauntingly subjective. Assessment, too, becomes time consuming if it entails detailed suggestions for improvement, but the holistic method can make it more efficient. Analytical grading (which calls for marking detailed lists of criteria) is more time consuming but provides important feedback that can lead to more confident student revisions. Ultimately, however, the strength of a good piece of writing is its overall impact, which is always to some extent subjective.
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In the Classroom
Evaluation of writing will always require time, but it is a task that becomes easier with practice. A well-constructed assignment will make the success criteria clear to students, thus simplifying holistic grading. In large measure, holistic evaluation is merely a formalization of the reader’s instinctive judgment of a piece of writing. If the essay reads smoothly and conveys the author’s points clearly, it should receive a high mark. If the reader must struggle to extract the meaning from a tangle of poorly-written sentences, the paper is clearly inadequate. Our experience is that with practical guidelines, such as those provided in our handbook, and a little experience, both faculty and teaching assistants can become efficient holistic graders of student writing. While grading is essential in most courses, assessment and appropriate feedback are equally important, for they show students how to improve their writing. The instructor’s response to a piece of writing opens a dialogue on the writing process, which in the best cases ultimately becomes each student’s internal dialogue—expression on the keyboard or sheet of paper, followed by questioning that expression, followed by revision. Some responses can be quick and easy; others are quite laborious. As with grading, a method can be devised that, with practice, will facilitate this dialogue and overcome the constraints that most faculty feel. Another method for responding, especially early in the semester, is to structure peer reviews of student writing. Students can be given specific criteria for helping their peers to improve. Less formal peer-review practices can be encouraged in team or group writing practices. Students often respond more positively to peer critique than to faculty suggestions. Our handbook is intended to offer guidance for grading, for responding, and for designing assignments. In addition to general guidelines for assignment design, busy faculty need assignments that can be used verbatim or with minor modification. Faculty who want to design their own assignments need good models. After all, most chemistry faculty learned to write problem sets and examinations from problems in standard textbooks or exams constructed by senior colleagues. A major part of our project has been to design for and collect in the handbook sample assignments for use in each of the core chemistry courses. The preliminary version of the handbook contains a number of such assignments, but more are needed. If you would like to contribute successful assignments, your submission will be welcomed and credited in the final edition of Writing Across the Chemistry Curriculum. Conclusion In spite of broad agreement that writing is an essential professional skill for chemists, few successful efforts to incorporate writing systematically into the chemistry curriculum have been documented. The writing across the curriculum movement has made some connections between writing and
chemistry teachers, but these often dissipate after the initial enthusiasm wanes. The goal of our project has been to create practical, easy-to-use materials that speak to chemistry faculty with minimal jargon. Our handbook addresses the three major problems—assignment design, strategy, and grading—and offers a substantial collection of model assignments. It also has an annotated bibliography of work in the relevant composition and rhetoric and chemical education literature. The preliminary edition, available from the authors, is currently under revision. Acknowledgments We are grateful to the Camille and Henry Dreyfus Foundation; the University of Tennessee, Knoxville; The Hodges Better English Fund; and the Knoxville-Oak Ridge Chapter of the Society for Technical Communication for financial support of this project. We thank Roger Jones for reading earlier versions of this article and making valuable suggestions for its improvement. Literature Cited 1. Hanson, D. M.; Wolfskill, T. J. Chem. Educ. 1998, 75, 143–147. 2. Zinsser, W. Writing to Learn; Harper & Row: New York, 1988 3. Bizzell, P.; Herzberg, B. In The Territory of Language; McQuade, D. A., Ed.; Southern Illinois University Press: Carbondale and Edwardsville, 1986; pp 340–352. 4. Shires, N. P. J. Chem. Educ. 1991, 68, 494–495. 5. Coppola, B. P.; Daniels, D. S. Sci. Educ. (Boston) 1998, 7, 31–48. Also see Kovac, J.; Coppola, B. P. Universities as Moral Communities; Soundings: An Interdiscipl. J., in press. 6. Bodner, G. M. J. Chem. Educ. 1991, 68, 385–388. Nakleh, M. B. J. Chem. Educ. 1992, 69, 191–196. 7. Reif, F.; Larkin, J. H.; Brackett, G. C. Am. J. Phys. 1976, 44, 212–217. Cognitive Process Instruction; Lochhead, J.; Clement, J., Eds.; Franklin Institute: Philadelphia, 1979. Hanson, D. M. An Instructor’s Guide to Process Workshops; Department of Chemistry, SUNY Stony Brook: Stony Brook, NY, 1996. Apple, D.; DuncanHewitt, W. A Primer for Process Education; Pacific Crest Software: Corvallis, OR, 1995. 8. Dodd, J. S., Ed.; The ACS Style Guide, 2nd ed.; Dodd, J. S., Ed.; American Chemical Society: Washington DC, 1998. 9. Kovac, J.; Sherwood, D. W. Writing Across the Chemistry Curriculum: A Faculty Handbook; The University of Tennessee: Knoxville, 1998. Copies of the preliminary edition of the handbook are available from the authors. 10. Bean, J. C.; Drenk, D.; Lee, F. D. In New Directions for Teaching and Learning: Teaching Writing in All Disciplines, No. 12; Griffin, C. W., Ed.; Jossey-Bass: San Francisco, 1982; pp 27–38. 11. Ebbing, D. D. General Chemistry, 5th ed.; Houghton Mifflin: Boston, 1996. 12. Kovac, J. J. Chem. Educ. 1999, 76, 120–124. 13. Hoffmann, R.; Coppola, B. P. J. Coll. Sci. Teach. 1996, 25, 390. 14. Kiniry, M.; Strenski, E. Coll. Compos. Commun. 1985, 36, 191–202. 15. Rosenthal, L. C. J. Chem. Educ. 1987, 64, 996–998.
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