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Resources for Student Assessment
Thomas A. Holme University of Wisconsin–Milwaukee Milwaukee, WI 53201
A Test Construction Support System for Chemistry Teachers
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Derek Cheung Department of Curriculum and Instruction, The Chinese University of Hong Kong, Shatin, Hong Kong;
[email protected] To teach chemistry effectively, teachers need to assess student learning in the various stages of the teaching process. They have to construct tests to assess students’ entry performance, learning progress, and end-of-instruction achievement. Five basic assessment methods are often used in secondary schools: selected response, essay, performance assessment, personal communication, and portfolio (1). However, it is important to note that no single method can assess the full range of learning targets for chemical education; multiple assessment methods must be used. The most common type of selected response items is the multiplechoice format, which can serve as a valid, reliable, and efficient tool to assess chemistry students’ knowledge and reasoning proficiency. Unfortunately, most secondary-school chemistry teachers have little training in educational assessment. They generally lack the requisite knowledge of itemwriting guidelines. Poorly written multiple-choice items will introduce errors and thus lower the dependability of test scores. More importantly, poorly written multiple-choice items cannot provide teachers with useful information to inform teaching and learning. The lack of teacher training in assessment has been discussed extensively in the literature (2–4). It is common knowledge that the correct answers should be distributed evenly among the alternative positions of multiple-choice items, but there are many other important guidelines for writing good items (5, 6). As Hopkins (7) pointed out, virtually all teacher-made tests contain violations of those guidelines. Teachers are rarely offered rigorous and useful training in assessment. Few programs of undergraduate education for prospective teachers include a course in measurement (8). However, Stiggins and Conklin (4) reminded us that relevant undergraduate and graduate courses represent only part of the answer because we must also plan to deliver assessment training to those millions of teachers who completed undergraduate and graduate programs that included no assessment training. Half-day “hit-and-run” inservice courses are ineffective to help practicing teachers master sound assessment techniques because research (9) suggests that professional development is likely to have a positive impact only if it is both sustained over time and involves a substantial number of hours. In this article, I report how a new Windows-compatible computer system called Test Construction Support System (TCSS) has been used to enhance the professional growth of new and experienced secondary-school chemistry teachers.
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Features of TCSS TCSS is a technology-assisted formative assessment tool (10). Visual Basic for Applications (VBA), Active Server Page (ASP), and Hypertext Markup Language (HTML) were used to code TCSS. TCSS has two application programs: (i) a Webbased application that enables students to self-assess their chemistry learning formatively and teachers to manage databases stored on servers in their schools and (ii) a stand-alone application that enables teachers to search for literature on student misconceptions in chemistry, to develop skills in test construction, and to design Web-based formative assessments. Although TCSS shares a number of features in common with other software such as WebCT and Classtalk, the Infobases and Teacher Exercises components of TCSS are unique. In this section, I briefly describe the main features and functions of these two components. Additional information about TCSS is available in the Supplemental Material.W
Infobases The term “infobases” stands for information databases. There are several databases in the stand-alone application of TCSS. The database called Writing MC Stems and Choices focuses on 15 guidelines for constructing multiple-choice items and examples are provided to demonstrate how these guidelines can be applied to construct quality chemistry items. Many sources (11, 12) are available describing how multiplechoice items should be constructed, but few use chemical education to illustrate item-writing guidelines. Therefore, this database is a self-instructional package for chemistry teachers to develop skills in test construction. No attempt will be made here to provide a detailed description of the 15 guidelines (Box 1), since they are available elsewhere (5–7). The single most important skill in constructing good multiple-choice items is the ability to design plausible distractors (7). Student misconceptions in science can serve as excellent distractors (13). Although researchers (14, 15) have successfully identified student misconceptions in a number of chemistry topics, secondary-school chemistry teachers are generally unaware of these important research findings. Also, current journals generally fail to communicate with teachers of their findings (16). TCSS has a database called Students’ Misconceptions. Teachers can access a total of 78 abstracts of publications. These publications are journal articles or conference articles published from 1957 to 2001. They were found from databases such as ERIC, but only those publications containing information about student misconceptions in electrochemistry, acid–base chemistry, or chemical
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Box 1. Guidelines for Writing Multiple-Choice Questions • The stem should be meaningful by itself and should present a definite problem. • Avoid using internal or beginning blanks in completion-type items. • The stem should include as much of the item as possible and should be free of irrelevant material. • Use a negatively stated stem only when significant learning outcomes require it and emphasize the negative term. • Irrelevant difficulty should be avoided. • All the options should be grammatically consistent with the stem and punctuated correctly. • Develop plausible distractors. • An item should contain only one correct or best answer. • Verbal associations between the stem and the correct answer should be avoided. • The relative length of the options should not provide a clue to the answer. • Avoid using “all of the above” or “none of the above” as an option. • Options should not be overlapped. • Avoid using absolute terms in the distractors. • Place options in logical or numerical order. • Avoid the use of complex multiple-choice format.
Box 2. Explanatory Note Accompanying an Example Item The reaction PCl5(g) PCl3(g) Cl2(g) is at equilibrium in an empty reactor fitted with a movable piston. What will happen if some argon (an inert gas) is added to the equilibrium mixture at constant pressure and temperature? A. The equilibrium will shift so that more PCl5(g) molecules will decompose to form PCl3(g) and Cl2(g). B. The total pressure will increase instantaneously and thus the equilibrium will shift to produce more PCl5(g). C. No effect will occur because argon does not react with any of the chemicals in the equilibrium mixture. D. More PCl3 molecules will combine with Cl2 to form PCl5 molecules to reduce the total volume. Note: The best answer is A. Research has confirmed that this is a hard question. Many students have the misconception that the addition of an inert gas never disturbs the equilibrium because there is no reaction between the inert gas and any of the chemicals involved in the reaction (i.e., option C). Also, some students may misapply Le Châtelier’s principle. They have the misconception that the addition of argon gas increases the total pressure and this increase in pressure will be minimized if the equilibrium counteracts in such a way that fewer gaseous molecules are present (i.e., option B). Besides, some students may select option D because they think that the equilibrium should counteract to reduce the number of gaseous molecule or volume. Actually, application of the equilibrium law should predict a right-side shift of the equilibrium in order to keep the Kc constant. For more information, see QuílezPardo and Solaz-Portolés (1995), and Furió, Calatayud, Bárcenas, and Padilla (2000).
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equilibrium were included in TCSS. Student misconceptions are summarized in each abstract. The 78 abstracts are keyword searchable. In addition, 47 concrete examples are available from the database called Example Test Items to illustrate how teachers can utilize student misconceptions in electrochemistry, acids–bases, and chemical equilibrium to design plausible distractors for multiple-choice items. In each example, a note is included to explain the rationale of the inclusion of a particular distractor, with hyperlinks to the relevant abstracts of publications. Box 2 shows one of the 47 examples. Option C is an excellent distractor. It is worth noting that application of Le Châtelier’s principle cannot solve this equilibrium problem. Because the system is kept at constant pressure and temperature, the argon gas will increase the total volume of the mixture and the concentrations of all gaseous reactants and products will reduce. According to Le Châtelier’s principle, the equilibrium system should counteract to increase the concentrations. However, if we apply Le Châtelier’s principle, different directional effects on the equilibrium must result; the decrease in the concentration of PCl5(g) requires that the position of equilibrium undergoes a left-side shift while the decrease in the concentrations of PCl3(g) and Cl2(g) requires a right-hand shift. Thus, Le Châtelier’s principle fails to give a definite answer to the question shown in Box 2. If we apply the concept of reaction quotient, option A is the only logical answer. See Cheung (17) for an extended discussion of the limitations of Le Châtelier’s principle.
Teacher Exercises As described in the preceding section, chemistry teachers can learn 15 important guidelines for writing good multiplechoice questions through TCSS. TCSS has the technology for enabling a chemistry teacher to self-assess his or her own level of understanding of those 15 guidelines. In the component called Teacher Exercises, each teacher is provided with opportunities to apply the 15 guidelines to evaluate the quality of 60 chemistry multiple-choice items. The 60 self-assessment questions are in a select-answer format and are programmed as four computer-based interactive exercises (Figure 1). Teachers are advised to start with Exercise 1 because Exercise 4 is the most challenging. TCSS keeps track of teacher responses and provides instant feedback through pop-up windows. TCSS uses the logon to create a unique record of performance for each teacher. When a multiple-choice item is displayed (see the top half of Figure 1), a teacher needs to click the OK button if it is well designed according to the 15 guidelines. For a faulty item, the teacher’s answer is counted as correct only if he or she has clicked the NOT OK button and selected the specific rule(s) violated. TCSS provides immediate feedback on the screen, including samples of revised items. This kind of self-assessment is one good way to allow chemistry teachers to develop skills in construction of quality multiple-choice items. In the example shown in Figure 1, the stem of the multiple-choice question does not present a definite problem and fails to force the options to be parallel in type of content. Ways to make the stem become more focused are demon-
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strated with two examples (Figure 2). Unfocused multiplechoice items are a frequent type of error made by teachers. Students do not obtain the intent of the item after reading the stem. When an exercise is finished, a summary of results will be displayed, showing the number of questions attempted, the number of questions that were answered correctly, and the percentage of correct responses. The teacher can quit an
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exercise any time he or she likes and TCSS can retrieve the unanswered questions whenever the teacher attempts the exercise again. To restart the exercise from the first question, all the teacher has to do is to click the Reset Exercises button (Figure 1). After a teacher has attempted the four exercises, she or he may have difficulties mastering a few guidelines for constructing multiple-choice items. TCSS provides two ways to
Figure 1. Exercises for teachers to develop skills in test construction.
Figure 2. Feedback given to teachers when they interact with self-assessment questions.
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Figure 3. Two modes of revision for teachers.
generate revision exercises to meet the teacher’s special needs (Figure 3). A subset of the 60 self-assessment items can be randomly retrieved from the database or all the self-assessment items that violate a particular rule can be retrieved for review. Thus, the Teacher Exercises component of TCSS provides an innovative learning environment for chemistry teachers—authentic, self-instructional, portable, and interruptible. Trials and Evaluations of TCSS TCSS version 1.0 was field tested in three schools. Four classes of Secondary 4 chemistry students and one class of Secondary 7 chemistry students participated in a trial of the Web-based application of TCSS. A total of 161 students were involved and they were of mixed ability. Students were asked to try at least two exercises installed on their school servers
and filled in an evaluation questionnaire (Table 1). Most of the participating students rated the Web-based application positively. For example, 89.5% of the students agreed or strongly agreed that they gained a better understanding of the chemical concepts after attempting the multiple-choice questions (item 5). Furthermore, a subset of the 161 students was interviewed after the trial. From class lists, two students were randomly selected from each of the Secondary 4 class and four students from the Secondary 7 class. Each of the 12 students was interviewed separately for about 15 minutes and was asked to respond to two open-ended questions: “Do you think TCSS can enhance your learning of chemistry?”, and “Any suggestions for further improvement of TCSS?”. The interviews revealed that students were positive to the use of TCSS and the benefits of TCSS that students provided can be categorized into three groups: self-learning, self-assessment, and flexibility (Box 3). Seven of the 12 students suggested that TCSS could cover more topics to help them review chemical concepts. Two students suggested that videos might be inserted to demonstrate some experiments. Clearly, student feedback from both the questionnaire survey and interviews indicates that TCSS is an effective learning tool for chemistry students. The three chemistry teachers of these three schools were also interviewed after the trial. They all thought that the Webbased application of TCSS was valuable. Their main reasons were (i) TCSS can generate user accounts for a class of students efficiently; (ii) I now know how to use the school server to enhance student learning of chemistry through the construction of meaningful Web-based multiple-choice items; (iii) TCSS can save me a lot of time to mark students’ assessment tasks; (iv) the statistical reports can reveal the misconceptions that students still possess after my instruction; and (v) TCSS is a cost-effective way to put “assessment for learning” into practice in my school. For the stand-alone application of TCSS, these three teachers believed that the system was effective. They found
Table 1. Student Evaluation of the Web-Based Application of TCSS
a
Percent Strongly Disagree
Item
Disagree Undecided
Agree
Strongly Agree
1. The multiple-choice questions are useful for me to review chemistry.
00.6
02.5
05.0
59.0
32.9
2. The page’s presentation is good.
00.6
06.2
09.3
67.7
16.1
3. The response time (i.e., the time lag between your request and the response by the computer) is acceptable.
01.2
05.0
09.9
59.0
24.8
4. The figures and photos can help me understand the questions.
01.2
05.6
13.0
47.8
32.3
5. I gained a better understanding of the chemical concepts after trying the multiple-choice questions.
00.0
03.1
07.5
67.1
22.4
6. The program has many “bugs” which cause it to behave inconsistently b or to “crash”.
34.8
50.9
08.7
03.7
01.9
7. The multiple-choice exercises are good for assessing my own learning of chemistry.
00.0
03.1
08.1
57.8
31.1
8. Screen display is clear and easy to read.
00.6
03.7
05.6
70.2
19.9
9. The feedback, hints and explanations are useful.
00.6
03.1
07.5
45.3
43.5
01.2
01.9
03.7
59.0
34.2
10. I want to try more of this kind of multiple-choice exercise in the future. a
TCSS version 1.0 (n = 161).
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b
Question 6 is negatively phrased.
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that the four interactive teacher exercises were innovative, excellent self-learning tools to enhance their competencies in educational assessment. Although they made a lot of mistakes when they attempted the four exercises, the teachers reported that they had learned a lot from them. For example, they were surprised to learn that several item formats that are often used by textbook writers are faulty; these item formats even appeared in public examination papers. Also, they liked the Teacher Exercises component because they were allowed to determine their own study paths and to review a particular guideline easily. Other positive comments given by the three teachers include: the idea to make use of students’ common misconceptions of chemistry to design distractors for multiple-choice item is excellent; all the illustrative examples of faulty multiple-choice items focus on chemistry; the literature on student misconceptions in chemical equilibrium, acids and bases, and electrochemistry is comprehensive; the abstracts of journal articles complied by TCSS make me think; and the item banks provide teachers with adequate flexibility. TCSS version 1.0 was distributed to other secondaryschool chemistry teachers when they attended two seminars. A questionnaire was used to survey their perceptions of the usefulness of TCSS. Table 2 summarizes 188 teachers’ responses to the questionnaire. Overall, teacher responses were encouraging. For example, 89.9% of the teachers agreed or strongly agreed that TCSS can facilitate teachers’ self-learning of guidelines for writing good multiple-choice items (item 5); 84.5% of the teachers agreed or strongly agreed that through TCSS, teachers can easily search for students’ misconceptions in chemical equilibrium, acids–bases, and electrochemistry (item 6); and 83.9% of the teachers agreed or strongly agreed that the item bank can provide teachers with good examples of formative assessment (item 8). Teacher responses to item 6 also indicate that TCSS has successfully built a bridge across the gulf between researchers and teachers by summarizing literature on student misconceptions in chemistry.
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Box 3. Excerpts from Interviews with Chemistry Students
Self-Learning • It’s good to try the TCSS. I made a lot of mistakes but that didn’t matter because I knew why! The system provided instant feedback and explanations. • Hints were shown on the screen when I needed them. I didn’t have to guess! This is good for selflearning. Also, I could check the hints before I clicked another choice. This gave me a lot of selfconfidence. • TCSS is an effective system to review chemistry because the multiple-choice items are subtopicspecific.
Self-Assessment • It’s nice to have an opportunity to self-assess whether I understood the chemical concepts taught by my teacher. • TCSS provides a stimulating learning environment. Answers were provided immediately. I didn’t have to wait for my teacher’s marking.
Flexibility • It’s easy to access the TCSS multiple-choice exercises through the Internet. • TCSS allows me to review chemistry at my own pace. Note: Twelve students were interviewed.
However, not all of the 188 teachers’ comments were positive, as revealed by comments that some teachers provided in the “open response” section of the questionnaire. The following quotations can illustrate the nature of their
Table 2. Teacher Evaluation of TCSS Percent Strongly Disagree
Item
Disagree Undecided
Agree
Strongly Agree
1. The Web-based multiple-choice questions are useful formative assessments.
0.0
0.5
02.1
69.5
27.8
2. The figures and photos can help students understand the multiple-choice questions.
0.0
0.5
13.8
68.1
17.6 27.7
3. The contents are relevant to the chemistry curricula in Hong Kong.
0.5
0.0
10.6
61.2
4. TCSS page’s presentation is good.
0.0
2.1
13.9
64.2
19.8
5. TCSS can facilitate teachers’ self-learning of guidelines for writing good multiple-choice items.
0.0
0.5
9.6
62.2
27.7
6. Through TCSS, teachers can easily search for common student misconceptions in chemical equilibrium, acids and bases, and electrochemistry.
0.0
0.0
15.6
56.5
28.0
7. TCSS is “user friendly”.
0.0
3.2
19.1
61.2
16.5
8. The item bank provides teachers with good examples of formative assessment.
0.0
1.1
15.0
63.6
20.3
9. Overall, TCSS is useful for chemistry teachers.
0.0
1.1
05.9
67.0
26.1
NOTE: TCSS version 1.0 (n = 188).
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Conclusion
major concerns: I definitely agree that TCSS is useful. But the main challenge for me is to find extra time to design the Web-based multiple-choice items. TCSS could include more sample items and cover a few more topics. Yes, both the Web-based application and stand-alone application of TCSS are innovative teaching-learning tools for chemical education. However, I teach chemistry in a Chinese school. A Chinese version should be available. TCSS stimulated my interest in formative assessment. I’m sure TCSS can guide me to develop high-quality assessment items. But it will require considerably more preparation time. I’m afraid I can’t finish the syllabus.
Chemistry teachers have high workload pressures. It is important to note that the validity of assessment results will be increased if teachers construct their TCSS Web-based multiple-choice items because the items can assess those chemical concepts that have been emphasized during instruction. The gain in item quality would pay for the extra investment of time. Based on the trials and evaluation results, TCSS was enhanced to include a total of 172 Web-based multiple-choice questions. Twenty-eight new chemistry teachers were invited to pilot-test TCSS version 2.0. Their feedback is summarized in Table 3. The teachers were supportive of the use of TCSS. In the “open response” section of the questionnaire, 7 of the 28 teachers pointed out that the Infobases and Teacher Exercises components are good because there are many practical aspects of constructing quality multiple-choice items and they are also helpful to physics and biology teachers. After the TCSS project was completed, the TCSS version 2.0 software and a 56-page User’s Guide were distributed to all secondary-school chemistry teachers in Hong Kong free of charge.
Good chemistry teaching cannot exist without good assessment because the assessment results can provide feedback to students on their achievement and to teachers on their teaching effectiveness. However, teachers untrained in educational assessment often make errors when they construct assessment items. The results of trials of TCSS were overwhelmingly positive regarding the usefulness of the system. Understanding the 15 guidelines is enormously helpful to teachers when they prepare multiple-choice items. For example, careful teachers should avoid using unfocused stems. Distractors chosen for multiple-choice items should reflect common misconceptions or incomplete learning observed among chemistry students during instruction. TCSS will not only improve chemistry teachers’ skills in test construction but also encourage teachers to reflect on their classroom teaching by exposing them to research on student misconceptions in chemistry. When teachers understand the common misconceptions in topics such as electrochemistry and chemical equilibrium, they may suitably modify their teaching methods to facilitate students to experience conceptual change. If additional resources are available, it is highly feasible to extend the Infobases component of TCSS by including other chemistry topics and to develop a Chinese version of TCSS. Further research is also being planned to determine the effects of the use of TCSS upon student performance in the end-of-year summative assessment. Acknowledgments The author would like to thank the Quality Education Fund for financial support of this project. Thanks are due to Fong-lok Lee and Raymond Wong for their help in the conduct of this research and the Hong Kong Examinations and
Table 3. Teacher Evaluation of TCSS Percent Strongly Disagree
Item
Disagree Undecided
Agree
Strongly Agree
1. The Web-based multiple-choice questions are useful formative assessments.
0.0
0.0
00.0
32.1
67.9
2. The figures and photos can help students understand the multiple-choice questions.
0.0
0.0
10.7
35.7
53.6
3. The contents are relevant to the chemistry curricula in Hong Kong.
0.0
0.0
00.0
53.6
46.4
4. TCSS page’s presentation is good.
0.0
0.0
00.0
82.1
17.9
5. TCSS can facilitate teachers’ self-learning of guidelines for writing good multiple-choice items.
0.0
0.0
00.0
50.0
50.0
6. Through TCSS, teachers can easily search for common student misconceptions in chemical equilibrium, acids and bases, and electrochemistry.
0.0
0.0
00.0
57.1
42.9
7. TCSS is “user friendly”.
0.0
0.0
00.0
78.6
21.4
8. The item bank provides teachers with good examples of formative assessment.
0.0
0.0
00.0
64.3
35.7
9. Overall, TCSS is useful for chemistry teachers.
0.0
0.0
00.0
32.1
67.9
NOTE: TCSS version 2.0 (n = 28).
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Assessment Authority for permission to reproduce past exam questions. W
Supplemental Material
Additional informaton about TCSS and the TCSS software and user’s guide is available in this issue of JCE Online. Literature Cited 1. Stiggins, R. J. Student-Involved Assessment for Learning, 4th ed.; Pearson Education: Upper Saddle River, NJ, 2005. 2. Plake, B. S.; Impara, J. C. Teacher Assessment Literacy. In Handbook of Classroom Assessment; Phye, G. D., Ed.; Academic Press: San Diego, 1997; pp 53–68. 3. Stiggins, R. J. Phi Delta Kappan 2002, 83, 758–765. 4. Stiggins, R. J.; Conklin, N. F. In Teachers’ Hands: Investigating the Practices of Classroom Assessment; State University of New York Press: Albany, NY, 1992. 5. Cheung, D. Hong Kong Sci. Teachers J. 2003, 21, 1–11. Also available at: http://www3.fed.cuhk.edu.hk/chemistry/(accessed May 2006). 6. Haladyna, T. M. Development and Validating Multiple-Choice Test Items, 3rd ed.; Lawrence Erlbaum Associates: Mahwah, NJ, 2004. 7. Hopkins, K. D. Educational and Psychological Measurement and Evaluation, 8th ed.; Allyn and Bacon: Boston, 1998.
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8. Mabry, L. Portfolios Plus: A Critical Guide to Alternative Assessment; Corwin Press: Thousand Oaks, CA, 1999. 9. Garet, M. S.; Porter, A. C.; Desimone, L.; Birman, B. F.; Yoon, K. S. American Educ. Res. J. 2001, 38, 915–945. 10. National Research Council. Knowing What Students Know: The Science and Design of Educational Assessment; National Academy Press: Washington, DC, 2001; Chapter 7. 11. Linn, R. L.; Gronlund, N. E. Measurement and Assessment in Teaching, 8th ed.; Merrill: Upper Saddle River, New Jersey, 2000. 12. Nitko, A. J. Educational Assessment of Students, 4th ed.; Pearson: Upper Saddle River, New Jersey, 2004. 13. Tamir, P. Assessment and Evaluation in Science Education: Opportunities to Learn and Outcomes. In International Handbook of Science Education; Fraser, B. J., Tobin, K. G., Eds.; Kluwer Academic Publishers: Dordrecht, The Netherlands, 1998; pp 761–789. 14. Garnett, P. J.; Garnett, P. J.; Hackling, M. W. Stud. Sci. Educ. 1995, 25, 69–95. 15. Taber, K. Chemical Misconceptions: Prevention, Diagnosis and Cure; Royal Society of Chemistry: Cambridge, United Kingdom, 2002. 16. Costa, N.; Marques, L.; Kempa, R. R. Sci. Tech. Educ. 2000, 18, 37–44. 17. Cheung, D. Hong Kong Sci. Teachers J. 2004, 22, 35–43. Also available at: http://www3.fed.cuhk.edu.hk/chemistry/ (accessed May 2006).
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