Theory and Experiment Laboratory - American Chemical Society

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Chapter 7

Theory and Experiment Laboratory: Modeling the Research Experience in an Upper-Level Curricular Laboratory Bridget L. Gourley* Department of Chemistry and Biochemistry, 602 South College Avenue, DePauw University, Greencastle, Indiana 46135, United States *E-mail: [email protected]. Phone: 765-658-4607.

While independent faculty mentored research projects are considered the gold standard for the undergraduate research experience (Laursen, S.; Hunter, A.B.; Seymour, E.; Thiry, H.; Melton, G. Undergraduate research in the sciences: Engaging students in real science; Jossey-Bass: San Francisco, CA, 2010), having all departmental majors gain experience with how new knowledge is built on existing literature and previous data has an important place in advancing undergraduate research and the education of students. This paper describes a round robin approach to a series of multi-week projects in a required upper-level laboratory for majors. As teams advance from one experiment to the next they build on the work of the previous team. The pedagogical vision is shared, how teams learn about the previous groups work is explained, sample projects are noted and insights about student gains based on students oral and written work are distributed.

© 2018 American Chemical Society Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

Introduction Institutional and Departmental Context The course being described in this paper is a capstone course for the chemistry major at DePauw University, a four-year residential private liberal arts institution located in Greencastle, Indiana. The institution, founded in 1837 by the Methodist Church has a 4-1-4-1 academic calendar with three-week terms in both January and May. The student body of 2200 students is 53% women, 20% declared minority students and 9% international. The first-year to second-year retention rate hovers near 90% and the four-year graduation is approximately 80% (1). The department has approximately 35 majors graduate per year of which five are chemistry majors and the other 30 are biochemistry majors. As with most departments of chemistry and biochemistry we serve the institution in a variety of ways, including approximately 200 unique students per year taking 100-level laboratory courses in the department each year, serving not only our own majors but biology and geoscience majors along with those pursuing a variety of pre-health interests. Additionally, the department regularly contributes to the first-year seminar program. Certified by the American Chemical Society (ACS), the department has 8 and 1/3 full-time equivalents (FTE) assigned. In 2002, the department launched a completely new curriculum shifting from the traditional linear path (Figure 1) through the curriculum to a curriculum that allows for multiple entry points and many trajectories (Figure 2). The old curriculum had the typical hierarchical year of general chemistry, year of organic chemistry, sophomore level courses in inorganic and analytical all required before taking a year of physical chemistry, instrumental methods of analysis and an advanced inorganic course.

Figure 1. Schematic illustrating pre-2002 curriculum illustrating linear path through the chemistry major. 102 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

Figure 2. Flowchart of pathways through the current introductory core.

DePauw uses a course credit system in which one course earns one credit and 31 credits are required for graduation. Non-laboratory courses typically meet for three hours per week and full credit laboratory courses in the department are scheduled for three class hours and three laboratory hours each week. In the catalog a DePauw credit is described as equivalent to a four-hour course at institutions with a credit hour distinction. The curriculum now begins with an introductory core of 4.25 credits taken by both the chemistry and biochemistry majors. A summary of requirements is given in Table 1. The core includes three separate full credit courses with laboratory that introduce students to the way inorganic, organic and biochemists view the discipline. Structure and Properties of Inorganic compounds (Chem 130) and Structure and Properties of Organic Molecules (Chem 120) can be taken in either order. Structure and Function of Biomolecules (Chem 240) requires Chem 120. The fourth course in the core, Thermodynamics, Equilibrium and Kinetics (Chem 260) has Chemical Stoichiometry (Chem 170), the 0.25 credit portion of the core and either Chem 120 or Chem 130 as pre-requisites. After the core chemistry majors select 1.5 course credits from three categories of advanced courses, Chemical Reactivity, Chemical Analysis, and Theoretical and Computational Chemistry. Course selections must include a laboratory course in each category. Students may also take elective courses in the Biochemistry category for the additional 0.5 credits of electives required for the major. Chemical Reactivity houses both inorganic and organic synthesis and reaction mechanisms. Chemical Analysis includes topics typically found 103 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

in analytical and instrumental methods courses. Theoretical and Computational Chemistry incorporates the components of Physical Chemistry and is where the Theory and Experiment upper-level 0.5 credit laboratory course described below is positioned. Other major requirements include the senior comprehensive exam based on the literature and mandatory seminar attendance.

Table 1. Requirements for the Chemistry Major Introductory Core (4.25 credits) • Structure and Properties of Organic Compounds (Chem 120) (1 credit w/lab) • Structure and Properties of Inorganic Molecules (Chem 130) (1 credit w/lab) • Stoichiometric Calculations (Chem 170) (0.25 credit; self-paced) • Structure and Function of Biomolecules (Chem 240) (1 credit w/lab) • Thermodynamics, Equilibrium and Kinetics (Chem 260) (1 credit w/lab) taken by both Chemistry and Biochemistry majors Categories for Advanced Courses • Chemical Reactivity (Mechanism and Synthesis) • Chemical Analysis (Analytical Chemistry) • Theoretical and Computational Chemistry (Physical Chemistry) • Biochemistry Chemistry Majors • 4.25 core credits • 4.0 cognate courses credits • 1.5 credits in each (including a lab in each category) o Chemical Reactivity o Chemical Analysis o Theoretical and Computational Chemistry • 0.5 additional elective credit • Senior Comprehensive Exam based on the chemical literature and seminar attendance

Course Overview Theory and Experiment (Chem 460) has three laboratory hours and one hour of recitation (or classroom time) per week. It is the only course in the Theoretical and Computational Chemistry category with a laboratory and so is effectively required of all chemistry majors, involving those who complete a senior research project and those who do not. A 300-level Chemical Kinetics, Chemical Thermodynamics, or Quantum Chemistry course is a pre- or co-requisite, helping to ground the experimental work. Students typically take this course as juniors or seniors. In early years of the new curriculum, the course was offered annually; over the last four years, the offering has been reduced to only even numbered years. The largest enrollment was nine students, while five or six is typical, and the course has been offered with as few as three students, in which they worked alone rather than in teams. 104 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

The catalogue description helps define for students the focus and approach of the course: “This project based laboratory will develop skills in asking fundamental questions about chemical behavior, deciding which theories can be used to explain that behavior, and then designing and implementing experiments to answer these questions (2).” In designing the course, I was motivated by a desire to provide all chemistry majors with some experience with how scientific progress is made, particularly since research is not required for the minimal B.A. The course should also give students practice building their own experiment based on the chemical literature and model experimental problem solving; in other words helping students learn how scientists establish confidence that data is meaningful as they learn a new experimental methodology. Additionally, I wanted the revised course to help students recognize core instrumentation that can be used to address multiple types of scientific questions. And finally, I aimed to create a paradigm that would keep the course dynamic and avoid getting stale. Considering how the rotation of experiments is envisioned, it is helpful to have a sense of some overarching structural issues. In a fourteen-week semester the first week of laboratory is an introductory week where we overview the course, check-in, and discuss laboratory safety. Some years, there are three projects each four weeks in length, while other years four projects are conducted each three weeks in length. The last laboratory session is used for clean-up and check out. Students work in groups of two or three and complete a group formal laboratory report for each experiment. Additionally, each group gives two oral presentations, a project update and a project finding during the recitation meetings over the course of the semester. Each student also writes an individual “memo to the boss” for each experiment performed. Table 2 provides the schedule for an example semester in which three four-week experiments were completed.

Round Robin Project Rotation During the first week, discussions about group dynamics are conducted reminding students of a previous course in the curriculum, Chem 260, where the laboratory work was completed in teams that stayed together throughout the semester and a series of ethical case studies about effective group work were discussed. Once teams for the semester are formed, the rotation begins with each team reviewing the project choices, handouts or procedural reference available on Moodle (our course management software) and submitting their ranked preferences. The instructor assigns each team a first experiment to avoid having more than one team on any experiment. In addition to avoiding duplicate need for the same equipment, assignment guarantees there are enough different experiments in the rotation to avoid a team rotating back to a previously performed experiment. For the second, project teams rotate to a project that was completed by another team during the first round (Figure 3).

105 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

Table 2. Theory and Experiments (Chem 460) Semester Schedule Semester Week

Main Recitation Activity

Laboratory Activity

1

Course intro, laboratory safety, oral & written report expectations

Written laboratory report workshop, Error propagation discussion

2

Project 1 (P1) week 1

Mathematica exercise

3

P1 week 2

Update presentations P1

4

P1 week 3

Software tips for laboratory reports

5

P1 week 4

Findings presentations P1

6


Grant proposal workshop

7

P2 week 2


8

Spring Break

No class

9

P2 week 3

Grant proposal review panel activity

10

P2 week 4


11


Introduction to convolution

12

P3 week 2


13

P3 week 3

Convolution exercises

14

P3 week 4


15

Clean-up, check out

Back-up presentations day

Figure 3. Illustration of laboratory round robin with sample experimental activity and procedural reference (3–7). 106 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

As a result of the project update and project findings presentations and class conversation teams and the instructor mutually agree on a rotation that guarantees that each group rotates to a new project. A key element of the approach is that teams share lessons learned during their oral presentations and provide recommendations for next steps. When a second group rotates onto the new experiment, they must first repeat an aspect of the first team’s work to demonstrate mastery of the technique and then decide on a new direction or extension of the work generating data that moves the project forward in some way; two examples follow. In one experiment, students measure the diffusion coefficients via laser diffraction; the first group might complete the experiment as described in J. Chem. Ed. (7) and the next team might choose to either study a different chemical system or perhaps refine the experimental design to improve the quality of the data. In the bomb calorimetry experiment, the first team might perform a relatively traditional estimate the resonance energy of a series of polycyclic aromatic hydrocarbons and a second group might decide to expand the series or shift to a completely different question that might logically be addressed via another calorimetric method, such as bomb, semi-micro, or solution calorimetry. For the third project, teams may rotate to a third experiment in the rotation or bring in a new experiment they would like to design. Groups may choose from an additional list of potential new experiments or submit an experiment from J. Chem. Ed. or other primary literature for approval. The additional list of potential experiments includes a few J. Chem. Ed. references that aim to inspire students to think about finding references for their own ideas. Criteria for experiment approval include that the institution owns the necessary instrumentation and, in the instructor’s best estimation, it is plausible to set up the experiment. Students must also demonstrate proof of concept and have sufficient data to write a formal laboratory report in the number of weeks allotted. Years when four experiments are included in the rotation, students have two potential opportunities to move to an experiment not previously done by other class teams. In the past, a new experiment introduced in the third rotation has been subsequently chosen in the fourth rotation by another team. As this course sits in the Theory and Computational Chemistry category for the major, it makes sense to choose experiments with an emphasis on physical chemistry. In any given year, there are a variety of approaches to kinetics, thermodynamics and spectroscopy, which sometimes is dependent upon changes in departmental instrumentation. Approximately 20 different experiments have been attempted over the ten separate offerings of the course to date. Kinetics experiments have included a variety of spectroscopic measurements of concentration as a function of time, method of initial rates, quenching and stopped-flow kinetics experiments. A Langmuir isotherm, calorimetry and three component phase diagrams are most often explored thermodynamic themes. Traditional quantum spectroscopy rounds out the other common experiments. Considering the successes and failures, there are seven experiments that are considered “tried and true” favorites and the initial first round offerings are typically selected from this list.


Vision for Project Work-flow Project work-flow is designed to model the research process and give students experiences similar to reporting out in research group meetings typically experience in graduate programs (Figure 4). Presentations during the recitation meeting time and regularly encouraging peer feedback further develop a collaborative group meeting atmosphere.

Figure 4. Progression of project activities illustrating how the various steps model the research process.

During the first two weeks of the project, teams set up their apparatus, make necessary solutions and gather enough data to demonstrate they have a working experiment. At the end of the second week, teams give an oral project update (described in more detail in the Oral report section below). One required component of the reporting is a description of planned next steps and/or challenges they are currently facing. Immediately following the report is a brainstorming session to address any challenges the team is facing or to ask probing questions that help teams refine their planned next steps. This interaction is similar to what might be experienced in a research group meeting at the graduate level when particular group members are updating others. The final two weeks of the project are spent collecting additional data to refine results. Groups are encouraged to begin writing the introductory and procedural sections of their formal laboratory reports. At the end of the last week of the project, teams prepare a second oral report, referred to as ‘project findings’ where they summarize results but are not yet required to have completed their error analysis. This is an opportunity to present their conclusions to the class who then function as a research group by asking questions about the data and conclusions, helping the team to think through what they need to discuss in order to produce a robust analysis in the formal report. 108 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

Formal reports are due early in the week following the experiment and, by that time, an error analysis and propagation is expected. Additionally, individual written ‘memo to the boss’ reports follow by the end of the week following. These memos are designed to ask students to use metacognitive thinking to address what they have learned over the course of the experiment, gain insight into the individual member contributions to the team’s work, and assure that all group members understand the project. Also, both oral reports serve to scaffold the formal report writing, with the project updates report helping organize the groups thinking with regard to their introduction and procedural sections and the project findings helping to frame the data analysis and conclusions.

Oral Report Foci and Purposes Project Updates Each team is expected to prepare a presentation of no more than ten minutes where they discuss what their experiment is measuring and how they are approaching the measurement. They are expected to explain some of the background theory, describe problems they have experienced to date, and suggest plans to address those challenges. These presentations are expected to take advantage of DyKnowTM, a tabletbased software used throughout the semester in this and related courses, that allows for mark-up and lecture capture of prepared slides for more informal interactions. Teams may have a couple of slides prepared that they annotate and we capture for their reference as well as all members of the class. Students can insert a blank slide to sketch ideas or hand write key equations or calculations. This contributes to a more informal conversation while allowing everyone to reference the content generated later as they reflect on next steps. As the semester progresses and the class hears a second and third group present background on the same project, teams begin to share additional aspects of the theoretical background so as to not just repeat what was heard in the previous round of project update presentations. As a result, by the time the rotations are completed, students gain an appreciation for a number of experiments, in many cases more than just those they performed during the semester.

Project Findings These presentations are more polished and likely have a collection of prepared slides. Teams are expected to share results requiring that their calculations are mostly complete. Teams typically show a sample calculation and then provide appropriate graphical or tabulated data summaries. It is a great opportunity for teams to organize the data and get feedback from their peers about whether the tables and/or figures they have prepared are effectively communicating what the laboratory group is hoping to illustrate. There is an expectation teams will provide 109 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

preliminary conclusions and float data interpretations to get feedback from their class peers who are the audience for the presentations. When the error analysis and propagation are still in progress, teams are expected to discuss sources of error. Hopefully this leads to discussion about whether or not they have identified the major sources of error to help focus their propagation calculations. Also, it often helps students determine whether the random nature of different trials or inherent measurement limitations define the outcome of their project. Finally, teams are expected to offer suggested future directions for the project. Since, in the next rotation, another group continues from where the presenting group ended the presenting group is encouraged to respond to the prompt, “if you had another three or four weeks to work on the project, what would you be most interested in exploring next and why.” The next group is not obligated to take the suggested direction, but the response gives a place to start. The groups are encouraged to consider and discuss the suggested next steps given the following week they need to move the project forward rather than just reproduce the same experiment. Because the course is designated to meet the DePauw requirements for a speaking and listening intensive course, students are also asked to complete a peer feedback survey for the project finding results. Comments from the peer feedback surveys are compiled and shared with the presenting team along with instructor feedback and scoring. Class members are asked to provide brief feedback to the following prompts:

• • • • •

Briefly summarize the presenters’ main results. What were the presenters’ main sources of error? Based on the presentation, what issues do you expect the presenters to raise in the discussion portion of their formal laboratory report? What was particularly helpful to you about the way the presenters shared their information? What else could the presenter have done to further develop your understanding of the experiment?

This survey is shared with the class when we discuss oral reporting and serves to further help frame the expectations for project findings. There is also a written course handout provided to students that further elaborates on oral report expectations and grading .

Written Report Contents Written handouts with expectations for both types of reporting are provided to students at the beginning of the semester.9 Additionally, a few sample anonymized formal reports, with an A, B and C level proficiency, from past semesters are provided. In a workshop fashion, students assess/score the reports based on 110 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

the rubric and we discuss their decisions between their first project update and project findings presentations. This usually leads to a better understanding of the complexity involved in both writing quality reports and evaluating reports.

Formal Written Reports These reports are traditional formal laboratory reports where students need to provide a title, abstract, introduction, experimental section, analysis of results, conclusion section, appendices and references. This is at least the second time in students experience in our curriculum where as a team they have had to compose a formal group report that included some of their own experimental design. Such an approach gives them further experience with an important skill used by most scientists today in academic, industrial, and national laboratory settings.

Informal “Memo to the Boss” These informal individual writings ask students to conversationally explain a project and how it fits into a bigger picture; provide a summary of the team results and describe their significance; address problems they encountered and suggestion resolutions; overview logical next steps and discuss what is the “personal value added.” The informal style of this writing piece is designed to help them practice the skill of casually discussing scientific work and find the balance of being able to conversationally use technical terminology. This particular piece is most clearly demonstrated when students explain how the project fits into a bigger picture. Summarizing results and describing significance is designed to assess whether or not they individually have taken ownership of the project and corresponding data analysis. Discussing the problems encountered, possible solutions, and logical next steps gives them the opportunity to agree with or deviate from the team consensus. Perhaps the most useful part is the value added section, which asks them to do metacognitive thinking about their own learning and how they have developed as a result of their work on this particular project. In some semesters, I have requested a student self-evaluation of their contribution and a description and evaluation of other members’ contributions. I value having students acknowledge their individual inputs. Also, at the beginning of the semester, those students who are worried about having to work in a group and whether or not everyone will “pull their weight” appear to appreciate knowing they have an official opportunity to provide feedback. However, I have found that this type of reporting often leads to some awkward group dynamics as the semester progresses. Consequently, in more recent iterations of the course, I have opted to omit those sections. I am considering adding back the self-reflection component of their own contribution to the group without the description and evaluation of others. 111 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

Project Grading Each project is worth 200 points divided up as follows: • • • • • •

30 points for actual laboratory work, e.g. time spent, quality and quantity of data 20 points for submitting laboratory notebook pages each week 25 points for the oral group project updates 35 points for the project findings presentation 60 points for the written formal team report 30 points for he written informal individual “memo to the boss”

The oral group project update, project finding presentation and written team report each receive one score received by every member of the team. Usually every team member also earns the same score with regard to the 30 points for laboratory work, although if I see a team member putting in noticeably more effort than other team members there may be a differential. Laboratory notebook pages and the “memo to the boss” are each graded based on the quality of the individual student’s submission. Use of Recitation (or Class) Time In addition to providing time for the project update and project findings presentations and discussion, alternate weeks are used to review error propagation, discuss effective presentation and graphical representation of data; workshop evaluating sample written reports; discuss software tips and tricks (including Microsoft Excel, Mathematica and other relevant software packages); examine grant proposals and conduct a mock grant proposal panel to expose students to another form of scientific peer review; and to learn about deconvolution of signals in data. The depth of coverage of these topics depends upon the skills students bring to the course, the post-baccalaureate plans of the students, and general student interest. For example, in some years, software tips and tricks consumed multiple recitation meetings while deconvolution of data was never really discussed. In other years, the grant proposal workshop and mock panel review spanned more than two class hours and software tips and tricks received little time.

Outcomes Some of the best evidence for the value of this approach comes from the “personal value added” section of the individual informal reports. In the quotes that follow all emphasis is added. The purpose of the italics and bold within the quotes is to highlight the portion of comments that specifically demonstrate achieving goals that motivated this course design. In a few cases, there are isolated quotes that speak to one motivation; more often the quotes speak collectively to a couple of the motivations. 112 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

I lead with a quote from several years ago that highlights the valued added to students when they pick-up the work of a previous group and move the project forward; it shifts student perspective from thinking of laboratory experiments as just something they need to get through as to having value. Additionally, it speaks to student’s freedom to put his or her own mark on the experiment. Finally I believe that being allowed to take what the previous group had completed compliments what we are able to put into the experiment. It was especially exciting when the previous groups data was so close to ours and still varied so much from the theoretical to find the “mistake” or misunderstanding of the manipulations of the data. – Student Fall 2010 As a physical chemist, I am always disappointed when students only see some of our major instrumentation such as NMR, IR, and GC-MS as tools solely for organic structure determination since that is the way in which they first encountered their utility in our curriculum. Evidence, such as the next quote, that demonstrate students gain new appreciation for the types of questions that can be answered a particular piece instrumentation is particularly gratifying as an instructor. My only experience with the NMR was to determine compounds based on ppm shifts. Other than figuring out the shifts of each component, it was interesting in a sense to find a new way to calculate the mole ratios just using peak integration. … It allowed me to think outside the box and to assume possibilities I wouldn’t have thought of otherwise.” – Student Spring 2016 In a variety of ways, the next few quotes demonstrate students becoming metacognitive about their learning and engaging in the overarching reflection that we want all students to do in all laboratory settings. By doing this experiment, I learned the importance of planning before the lab. My productivity of the first two lab time was not very high, but after I made plan before I went to the lab, the following two lab time has a really high productivity. [sic] – Student Fall 2012 From the Langmuir isotherm I plotted, I realized that I probably need not have done so many trials near the concentration where I assumed the surface sites were saturated because there wasn’t much variation in the Raman intensities for very similar concentration. – Student Fall 2012 I believe this lab deeply increased my own personal value: asking myself if the data made sense was the most contributing factor to this value increase. – Student from Fall 2010


Sometimes there were gains not anticipated at the outset. For example, while I always strive to help students understand the value of error analysis and propagation, most students see the task as drudgery and seldom really think about what the results of error propagation are telling them about their experiment. These next quotes illustrate student intellectual growth as a result of error analyses. This experiment allowed me to increase my knowledge of error analysis and how to apply it to new theories. The hand out given for this lab did not contain error statistics for their data. This allowed our group to formulate our error entirely based on where we personally thought error could have occurred. – Student from Fall 2010 The other aspect of this lab that I found to be useful was in understanding error propagation. Our goal of factoring in identified indeterminate sources of error by eliminating the thousandths and ten-thousandths place in our mass data caused huge errors to occur for measurements that were less than one gram. This simply suggests that a sample with mass of less than one gram have fewer “parts” that can be counted as significant. Thus, apparently small deviations lead to huge errors for measurements significantly less than one gram. – Student Fall 2010 My biggest take away from this experiment came from the data analysis and calculations. X and Y’s presentation emphasized the amount of work that went into their calculations in order to have accurate dissociation constants, so I was expecting a grueling calculation process. Then I reread the sample report on Moodle and noticed for their calculations they assumed a 5% protonation rate, and ignored the dissociation calculation for individual samples. Initially I was wary of this assumption and its impact on the final results, so I ran the calculation using X and Y’s data in order to determine how much the values actually varied as a result of the different calculation methods. The mass percentages had a percent difference of less than 1% for every single piece of data. Since the difference between the two methods was less than 1% I felt comfortable using the 5% protonation assumption for all of my calculations. The lesson here was that assumptions can provide results that are equally as valid (to the same significant figures), and they can make the calculations significantly less time consuming. – Student Spring 2016 This last quote demonstrates how many quotes focus on more than one of the core goals. While this student’s remarks are address error propagation calculations, they also provide a rich example of deep thinking about calculations and that perhaps it is unwise to just launch in to brute force a set of calculations. This quote also demonstrates a student who is invested in their learning, even 114 Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

to the point of redoing the calculations of a previous group in the rotation; this would be very unlikely without this course’s pedagogical focus. Finally, two last quotes demonstrate students delving deeper into the analysis of their data and recognizing skills that will allow them to be more independent researchers. These quotes also illustrate students making multiple gains within a single experiment and being conscious of these gains. This was not an easy lab at all, because our data often differed significantly from the predicted outcome. Therefore, we constant had to redo trials to get better results. However, this lab challenged us to think about our data and to reason out solutions [to] problems more than the XXX lab did. – Student Spring 2015 We had to try things out four times and get to the right ways. I think we have practice one of the most important skills in this experiment. When we had problems we suggested the ways to solve them. Even if it did not work for the first few times we still kept trying until we came up with the right solutions. This is a very important quality that we developed and will maintain in the future. Also touching on new things and being able to learn them are also impressive in this lab. As I mentioned earlier we did not have experience in YYY. Then we started reading literatures and asked questions and finally understood the things going on in this lab. In the future we would acquire new knowledge faster because we had experience with that. [sic] – Student Spring 2016 (Non-native English speaker) Many of the quotes above (and others not included in this manuscript) allude to the individual gains in experimental problem solving and figuring out whether or not the data being collected is providing meaningful results. There are no student comments that directly demonstrate that this round robin approach keeps the course from becoming stale. However, after the first rotation, I am never quite sure what students might choose to address as they build on what the previous team accomplished in the first round. This is perhaps the best evidence that this approach has kept the course from becoming boring. Personally, the course has kept me, as the instructor, intellectually on my toes and fully engaged in the wonder of discovery with the students. A couple of the quotes indirectly demonstrate that students are making links between the approach of this course and the progress of science more generally. A few comments hint at the value of utilizing the chemical literature to advance the experiment. Usually about 50% of the teams in any particular semester will choose to test an experiment their cohort has not done as the last experiment in the rotation. Most of the time they choose an experiment (or at least a twist on one) that has not been previously performed at DePauw. As there are two presentations with each project, all students gain from the inclusion of a new experiment by others.


Conclusions This approach to an upper-level laboratory engages all departmental majors at DePauw in a opportunity to experience the scholarly process and to learn how new knowledge is built on existing literature and previous data. This course develops students’ ability to resolve issues with data collection. Students come to appreciate the value of digging into the literature to see what others have done related to their project or might suggest new directions. Students also learn the process of building on the work of others. Students gain confidence they have built a collection of skills, intuition, and knowledge that will facilitate their ability to design and conduct experiments moving forward. Students become natural speakers about their work in front of a group. Faculty members can learn a great deal about where students are by asking them to reflect and share what they have learned. Summarizing the peer feedback, as well as providing instructor comments within a day of the project finding presentations, helps teams strengthen the quality of their formal reports. Asking students to self-evaluate their personal overall contribution to the group’s work provides additional useful metacognitive development. Asking students to provide reflection about other group member’s contributions, while potentially providing the instructor useful information and group member accountability, can also set up awkward group dynamics among team members as the semester progresses. Finally, this approach to an upper-level laboratory creates a dynamic and interesting class, enjoyed by both the students and the instructor.

Acknowledgments I gratefully acknowledge the DePauw University Theory and Experiment (Chem 460) students over the past 15 years. These students have been instrumental in helping me to refine handouts, rubrics, and experiments. In addition, I thank my departmental colleagues, tenured, tenure-track and term, who have helped develop this curriculum and prepared students for this upper-level laboratory course.

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DePauw University quick book 2017. https://www.depauw.edu/about/quickfacts/ (accessed March 12, 2018) DePauw University catalog. https://www.depauw.edu/academics/ departments-programs/chemistry-and-biochemistry/courses/ (accessed March 12, 2018) Garland, C. W.; Nibler, J. W.; Shoemaker, D. P., Experiments in physical chemistry, 8th ed.; McGraw Hill: New York, 2009; pp 436-446. Annis, D. A.; Collard, D. M.; Bottomley, L. A. Bromination of disubstituted arenes: Kinetics and mechanism: GC-MS experiments for the insturumental analysis and organic chemistry labs. J. Chem. Ed. 1995, 72, 460–462. 116

Gourley and Jones; Best Practices for Supporting and Expanding Undergraduate Research in Chemistry ACS Symposium Series; American Chemical Society: Washington, DC, 2018.

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Karukstis, K. K.; Avrantinis, S. K.; Boegeman, S. L.; Conner, J. N.; Hackman, B. M.; Lindsay, J. M.; Mandel, A. L.; Miller, E. J. Spectroscopic determination of ternary phase diagrams. J. Chem. Ed. 2000, 77, 701. Claasen, R.; Wolcott, R.; Reinbold, P. E. Study by NMR of a three-component system. A physical-organic experiment. J. Chem. Ed. 1978, 55, 542–544. Rinehart, F. P.; Sattar, S. Diffusion of CsCL in aqueous glycerol measured by laser refraction: A physical chemistry laboratory. J. Chem. Ed. 1998, 75, 1136–1138. Handout for students describing oral presentation requirements available from the author upon request. Handout for students describing written report requirements available from the author upon request.


Theory and Experiment Laboratory - American Chemical Society

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