Graphing Activity for the First General Chemistry Lab Session to

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Graphing Activity for the First General Chemistry Lab Session to Introduce Data Processing D. Brandon Magers,* Patricia L. Stan, and Daniel A. King* Department of Chemistry and Biochemistry, Taylor University, Upland, Indiana 46989, United States

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S Supporting Information *

ABSTRACT: The first day of lab was traditionally a day to check into lab drawers, discuss lab safety, and perform a basic primer in graphing with Microsoft (MS) Excel, but it now includes an activity that involves reproducing a rather complex graph from the scientific literature. The activity is designed to give the students a brief introduction to the layout of a scientific article; its similarity to the scientific process; and basic statistics, including mean and standard deviation. The task of reproducing the graph from the literature requires students to demonstrate their ability to perform calculations using MS Excel, plot multiple series on one graph, display trendlines, use a secondary axis, and employ custom error bars. The mastery of these skills is apparent to the students and instructors by inspection of the completed graph and grading of the spreadsheet and postactivity questions using a rubric that is specific to the learning outcomes (96.3% class average). Furthermore, the graph to be duplicated is chosen from a paper coauthored by an undergraduate from our university, which creates a sense of relevance to the students. Using an article from our institution also provides the advantage of having access to the raw data, which are not always found in the literature. The incorporation of this activity into the first lab session of our introductory first-year chemistry course has resulted in the instructors of this and subsequent courses to rarely need to assist students in creating graphs, which are the routine conclusion to many lab sessions. KEYWORDS: First-Year Undergraduate/General, Curriculum, Laboratory Instruction, Computer-Based Learning, Laboratory Computing/Interfacing, Quantitative Analysis



INTRODUCTION Exposing undergraduate chemistry students to research and the research process has become an important and, perhaps, essential aspect to any undergraduate chemistry program. In fact, the American Chemical Society requires research to be part of their certified programs, and the National Science Foundation (NSF) Division of Chemistry funds Research Experience for Undergraduate (REU) sites across the country,1 with a total REU budget request of $75.6 million in fiscal year 2017, 33% more than was requested one decade earlier, in 2007.2,3 The NSF’s support for REU programs “reflects the importance of undergraduate research experiences in building students’ interest and competence in STEM disciplines”.3 Studies have been performed to assess the value of undergraduate research experience, most of which emphasize the importance of the faculty mentoring process and helping students develop a vision for their future career paths.4−6 Additionally, one study found that 98% of participating students would recommend the experience to others.7 However, as valuable as undergraduate research experiences are perceived to be, they are often only available to a small number of students and provide exposure to only a small portion of the scientific process. Typical 8 week summer internships, which are competitive and not available for all © XXXX American Chemical Society and Division of Chemical Education, Inc.

students, are too short for students to significantly investigate the literature, develop a research question, learn the skills and knowledge needed to carry out the work, perform the work to some reasonable point of closure, and write a report.8 Consequently, there has been a strong push within the chemistry education community to integrate the research experience into the undergraduate curriculum to ensure every student has the opportunity to participate. Integrating research into the undergraduate curriculum is considered a high-impact practice with tremendous potential benefits beyond those of traditional pedagogy. Research integrated into the curriculum has the potential to more closely illustrate how the content within the curriculum is a natural outflow of past scholarship, excite students in the classroom with relevant and current research questions, and teach the scientific process as content and skills that need to be learned along with traditional chemistry knowledge.5,9−16 In an effort to lay the foundation for research oriented, exploratory experiments that follow within this and subsequent courses and to motivate students by creating relevance,17,18 the Received: March 15, 2019 Revised: June 5, 2019

A

DOI: 10.1021/acs.jchemed.9b00226 J. Chem. Educ. XXXX, XXX, XXX−XXX

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of a scientific article (Background, Experimental Methods, Results, Discussion, and Conclusions) mimic the scientific method (studying the literature, developing a question or hypothesis, designing and carrying out an experiment, evaluating the results, revising the hypothesis, and disseminating the information). Understanding that the layout of articles is often the same as the scientific method that they have learned about since elementary school makes it more intuitive for students to know where to go within an article to find the information for which they are looking. Next, students are presented with an introduction to data, statistics, and graphing. A very remedial lesson about normal distributions is provided so that students understand the meaning of a standard deviation when asked to perform this calculation in MS Excel. A simple normal curve is shown that emphasizes the relationship between the area under a curve and ±1 and 2 standard deviations around the mean (Figure 1).

activity described in this manuscript has been introduced into students’ first laboratory experience, session one of the firstyear chemistry laboratory (CHE211L).19 Where the first day used to be simply a check-in day in the laboratory, we have for nearly 10 years taken the opportunity to guide students through a remedial lesson on graphing with Microsoft (MS) Excel. The goal had been to teach the typical format and layouts that we will routinely expect for graphing results during subsequent laboratories. Then, after considering that first-year chemistry students can achieve competency in scientific literature,20,21 we had a desire to exposure students to scientific articles early and often in their first semester to establish the importance of the undergraduate chemistry laboratory and to create motivation by illustrating its usefulness and relevance to the students.17 Therefore, we have more recently integrated concepts and skills related to navigating a scientific article and performing basic statistics, which culminates in having students reproduce a graph from a scientific journal. Although many articles could be used, we chose to use a published paper coauthored by an undergraduate student from our university to build relevance and interest among the students and because we have access to the raw data. If an institution does not have a recent or appropriate published article, we encourage instructors to find an article that is particularly relatable to their students, for example, an article about the local geography. After the successful completion of the activity students should be able to • Perform calculations in MS Excel (mean and standard deviation) • Plot two series on the same graph • Display trendlines • Use a secondary axis • Employ custom error bars These learning outcomes are all assessed by students successfully completing the activity, creating two graphs, and answering the postactivity questions.

Figure 1. Generic normal curve. The values represent the percentage of the total area under the curve that lies within the ±1 and 2 standard deviation boundaries.

The first set of data that the students graph was created to simulate two sets of kinetic data, one reaction following a linear trend and one following an exponential trend. The primary goals of this exercise are for students to learn how to plot two series on the same graph and how to add trendlines. This step usually goes quite smoothly for the majority of students, and the instructors are only needed to help significantly with those who have very limited prior experience with MS Excel. The second and final graphing exercise is to re-create a more complex graph found in the article that was selected for the day, which requires the students to do a few initial calculations. This data set is provided for them in the form of triplicate measurements at varying distances from the source of a geothermal discharge. Students learn how to do replicate calculations by first calculating the mean and standard deviation of each set of triplicate measurements using the “=average()” and “=stdev()” functions, respectively, and then using the copy−paste or drag utility to apply the calculation to all sets of triplicate measurements (Table 1). The resulting graph is more complicated than the first in that it involves plotting two series ([Ca2+] and [Fe2+/3+]) on the same graph, both of which have such different values that using a secondary y-axis scale is necessary. Additionally, the values plotted are the means of replicate measurements (calculated by students), for which their standard deviations (also calculated by students) are used as error bars within the graph (Figure 2). The resulting graphs and answers to related postactivity questions are graded to ensure that all students understand these minimal yet essential skills. The rubric for



ACTIVITY Prior to the first laboratory session, students are supplied with a copy of the instructions for the activity, the report sheet (with questions to be completed at the end of the activity), the article22 that contains the graph they will be duplicating, and the raw data organized in an MS Excel spreadsheet. It is expected that the students will have read the instructions and the article and have MS Excel installed onto their personal laptop or computing device before arriving to lab. This activity is used in the laboratory setting, with four sections of approximately 18 students each. The sections are taught by full-time faculty. The session begins by sharing some typical introductory information about the course with the students. After familiarizing the students with the instructor, the course expectations found in the syllabus, and general safety guidelines for the laboratory, we begin the activity described in this manuscript. The activity begins with a presentation of the skills required to complete the activity: reading a scientific article, understanding basic normal statistics, and preparing a complex graph with MS Excel. Understanding that most of these students are first-semester university students, this is the first experience for most in reading a scientific article. Consequently, we briefly illustrate how the typical elements B

DOI: 10.1021/acs.jchemed.9b00226 J. Chem. Educ. XXXX, XXX, XXX−XXX

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Table 1. Portion of the Raw Data Provided for the Studentsa Ca2+(aq) (mg L−1) Distance from Source (m)

Sample 1

Sample 2

Sample 3

Average Calcium

SD

0 6 12 18 30 37 43 49 55 61 67 73 79 85

30.0233 32.2373 29.2639 30.6529 29.4489 26.1561 27.4939 29.2754 29.8079 27.2713 25.3797 24.2671 26.1501 25.1604

29.0663 29.3621 29.8447 30.6579 27.6853 27.9850 28.6067 28.6199 29.4317 27.4880 25.7325 26.2239 24.8647 26.1245

34.3969 28.7643 30.4290 32.1286 29.7330 29.3232 27.7031 29.6791 30.0880 30.1108 27.0295 25.7604 25.8400 25.8456

=average(B4:D4)

=stdev(B6:D6)

a

The data contain triplicate concentration measurements of calcium and iron (not shown) at varying distances from a geothermal discharge source.

Figure 2. Graph of iron (■) and calcium (□) concentrations along a geothermal discharge stream. Adapted with permission from ref 22. Copyright 2013 Indiana Academy of Science.

inspection. Instructors are able to assess the degree to which the learning outcomes (performing spreadsheet calculations, plotting two series on one graph, displaying trendlines, using a secondary axis, and employing custom error bars) are met at the end of the activity by the grading of the spreadsheet and postactivity questions. The high scores observed for this activity strongly suggest that the learning outcomes are being met by the vast majority of participating students. Duplicating a graph from the literature authored by an undergraduate peer was employed as an attempt to create motivation among the students, that they might view themselves as novice scientists and not as outsiders. Following the inclusion of this activity, instructors report no significant issues with students’ ability to produce appropriate graphs in subsequent laboratory sessions.

grading this activity includes 50% for completing the activity, 9% for correctly answering the three postactivity questions, 8% for properly calculating averages and standard deviations, 16% for properly creating graph 1 (4% for proper titles and axis labels, 4% for including the regression lines, 4% for including the equations and R2 values, and 4% for properly graphing the data), and 17% for properly creating graph 2 (5% for proper titles and axis labels, 6% for including error bars, and 6% for the correct scaling of the dual axes). This year, the 60 participating students had an average score of 96.3% and a median score of 100% on this activity. Additionally, the faculty have observed that since the introduction of this activity, students are well prepared for the graphing expectations throughout the remainder of the course as they rarely need assistance.





ASSOCIATED CONTENT

S Supporting Information *

CONCLUSION Incorporating a graphing exercise from the scientific literature early in the laboratory curriculum is an efficient way to introduce concepts of data processing. The successful completion of the graph and visual comparison to the literature version allows students and instructors to informally assess student progress during the activity by simple visual

The Supporting Information is available on the ACS Publications website at DOI: 10.1021/acs.jchemed.9b00226. Instructor Notes (PDF, DOCX) Instructions (PDF, DOCX) Report Sheet (PDF, DOCX) C

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(18) DeKorver, B. K.; Towns, M. H. General Chemistry Students’ Goals for Chemistry Laboratory Coursework. J. Chem. Educ. 2015, 92 (12), 2031−2037. (19) Kroll, L. Teaching the Research Process via Organic Chemistry Lab Projects. J. Chem. Educ. 1985, 62 (6), 516−518. (20) Bruehl, M.; Pan, D.; Ferrer-Vinent, I. J. Demystifying the Chemistry Literature: Building Information Literacy in First-Year Chemistry Students through Student-Centered Learning and Experiment Design. J. Chem. Educ. 2015, 92 (1), 52−57. (21) Ferrer-Vinent, I. J.; Bruehl, M.; Pan, D.; Jones, G. L. Introducing Scientific Literature to Honors General Chemistry Students: Teaching Information Literacy and the Nature of Research to First-Year Chemistry Students. J. Chem. Educ. 2015, 92 (4), 617− 624. (22) Griffiths, T.; Hart, E.; Stan, P.; King, D. Analysis of Iron and Calcium in a Geothermal System Outflow Stream. Proc. Indiana Acad. Sci. 2013, 122 (1), 35−39.

AUTHOR INFORMATION

Corresponding Authors

*E-mail: [email protected] (D.B.M.). *E-mail: [email protected] (D.A.K.). ORCID

D. Brandon Magers: 0000-0001-6002-0183 Patricia L. Stan: 0000-0003-2664-2995 Daniel A. King: 0000-0002-5993-0814 Notes

The authors declare no competing financial interest.



REFERENCES

(1) Chemistry Research Experiences for Undergraduates (REU). National Science Foundation. https://www.nsf.gov/funding/pgm_ summ.jsp?pims_id=503210 (accessed June 12, 2018). (2) NSF-Wide Investments. In FY 2007 NSF Budget Request to Congress; National Science Foundation, 2007; p 22. (3) NSF-Wide Investments. In FY 2017 NSF Budget Request to Congress; National Science Foundation, 2017; p 81. (4) Linn, M. C.; Palmer, E.; Baranger, A.; Gerard, E.; Stone, E. Undergraduate Research Experiences: Impacts and Opportunities. Science (Washington, DC, U. S.) 2015, 347 (6222), 1261757. (5) Hunter, A.; Laursen, S. L.; Seymour, E. Becoming a Scientist: The Role of Undergraduate Research in Students’ Cognitive, Personal, and Professional Development. Sci. Educ. 2007, 91 (1), 36−74. (6) Elgren, T.; Hensel, N. Undergraduate Research Experiences: Synergies between Scholarship and Teaching. Peer Rev. 2006, 8 (1), 4−7. (7) Mabrouk, P. A.; Peters, K. Student Perspectives on Undergraduate Research (UR) Experiences in Chemistry and Biology. CUR Q. 2000, 21 (1), 25−33. (8) Hunter, A. M.; St Clair Gibson, A.; Lambert, M. I.; Nobbs, L.; Noakes, T. D. Effects of Supramaximal Exercise on the Electromyographic Signal. Br. J. Sports Med. 2003, 37 (4), 296−299. (9) Martin, N. H. Integration of Computational Chemistry into the Chemistry Curriculum. J. Chem. Educ. 1998, 75 (2), 241−243. (10) Bauer, K. W.; Bennett, J. S. Alumni Perceptions Used to Assess Undergraduate Research Experience. J. Higher Educ. 2003, 74 (2), 210−230. (11) Richter-Egger, D. L.; Hagen, J. P.; Laquer, F. C.; Grandgenett, N. F.; Shuster, R. D. Improving Student Attitudes about Science by Integrating Research into the Introductory Chemistry Laboratory: Interdisciplinary Drinking Water Analysis. J. Chem. Educ. 2010, 87 (8), 862−868. (12) Barak, M. Transition from Traditional to ICT-Enhanced Learning Environments in Undergraduate Chemistry Courses. Comput. Educ. 2007, 48 (1), 30−43. (13) Ü ltay, N.; Ç alık, M. A Thematic Review of Studies into the Effectiveness of Context-Based Chemistry Curricula. J. Sci. Educ. Technol. 2012, 21 (6), 686−701. (14) Shaffer, C. D.; Alvarez, C.; Bailey, C.; Barnard, D.; Bhalla, S.; Chandrasekaran, C.; Chandrasekaran, V.; Chung, H.-M.; Dorer, D. R.; Du, C.; et al. The Genomics Education Partnership: Successful Integration of Research into Laboratory Classes at a Diverse Group of Undergraduate Institutions. CBELife Sci. Educ. 2010, 9 (1), 55−69. (15) Gabel, D. Improving Teaching and Learning through Chemistry Education Research: A Look to the Future. J. Chem. Educ. 1999, 76 (4), 548−554. (16) Smithenry, D. W. Integrating Guided Inquiry into a Traditional Chemistry Curricular Framework. Int. J. Sci. Educ. 2010, 32 (13), 1689−1714. (17) Roberson, R. Helping Students Find Relevance. Psychol. Teach. Netw. 2013, 23 (2), 18−20. D

DOI: 10.1021/acs.jchemed.9b00226 J. Chem. Educ. XXXX, XXX, XXX−XXX