General Chemistry I (CHEM 121) sets the foundation for the chemistry education of Valparaiso students; therefore, it is critical that the CHEM 121 lecture and laboratory courses provide rich learning experiences that are meaningful, focused and both academically and visually engaging. In this project, two new or significantly revised laboratory experiments were incorporated into the curriculum during the Spring 2018 semester for the first time: 1) The Limiting Reagent in Action: Determining the Formula of a Precipitate and 2) The Analysis of Microplastic Pollution in Local Soil. The common goal of both labs were to increase student understanding of challenging general chemistry concepts by enhancing student engagement. In the case of Experiment 1, this was accomplished by improving the visual appeal of the reactions employed; in the case of Experiment 2, this was accomplished by directly connecting course material to study real-world pollution problems facing NW Indiana. Results of this experimentation and its impact on student learning in CHEM 121 are described

Clark, Robert

Peller, Julie

Rowe, Laura

Statza, Emily

English

Valparaiso University

Valparaiso UniversityValpoScholarSymposium on Undergraduate Research andCreative Expression (SOURCE) Office of Sponsored and Undergraduate ResearchSpring 5-3-2018Enhancing General Chemistry Labs to ConstructEngaging, Colorful ExperimentsEmily Statzaemily.statza@valpo.eduRobert ClarkValparaiso University, robert.clark@valpo.eduLaura RoweValparaiso University, laura.rowe@valpo.eduJulie PellerValparaiso University, julie.peller@valpo.eduFollow this and additional works at: https://scholar.valpo.edu/cusThis Poster Presentation is brought to you for free and open access by the Office of Sponsored and Undergraduate Research at ValpoScholar. It has beenaccepted for inclusion in Symposium on Undergraduate Research and Creative Expression (SOURCE) by an authorized administrator of ValpoScholar.For more information, please contact a ValpoScholar staff member at scholar@valpo.edu.Recommended CitationStatza, Emily; Clark, Robert; Rowe, Laura; and Peller, Julie, "Enhancing General Chemistry Labs to Construct Engaging, ColorfulExperiments" (2018). Symposium on Undergraduate Research and Creative Expression (SOURCE). 690.https://scholar.valpo.edu/cus/690Limiting Reagent in Action:Enhancing General Chemistry Labs to Construct Engaging, Colorful ExperimentsEmily Statza, Dr. Clark, Dr. Peller, and Dr. RoweValparaiso UniversityAnalysis of Microplastic Pollution in Local Soil: Overarching Goal: Provide students with captivating laboratory experiments to solidify lecture material and connect their studies to real-world issues.    Discussion: Limiting Reagent:• Students gained a more complete understanding of limiting reactant stoichiometry• Multiple analysis modes provided students with several complementary approaches to solve a chemical problem• Experiment was more visually appealing by employing a transition metal that formed colorful compounds• Future Work: More fully investigate student conceptions about what constitutes compelling evidence Microplastic Pollution:• Students gained experience applying their classroom learning to perform experiments that address real-world issues• Students had a somewhat better perspective on how the research process works and what it means• Future Work: Increase student engagement by having students supply their own soil samples and hypothesize and present their resultsAbstract:General Chemistry I (CHEM 121) sets the foundation for the chemistry education of Valparaiso students; therefore, it is critical that the CHEM 121 lecture and laboratory courses provide rich learning experiences that are meaningful, focused, and engaging. In this project, two new or significantly revised laboratory experiments were incorporated into the curriculum during the Spring 2018 semester: 1) The Limiting Reagent in Action: Determining the Formula of a Precipitate and 2) The Analysis of Microplastic Pollution in Local Soil. The common goals of both labs were to increase student understanding of challenging general chemistry concepts by enhancing student engagement. For Experiment 1, this was accomplished by adding additional qualitative testing to study the reactions; in the case of Experiment 2, this was accomplished by directly connecting course material to study real-world pollution problems facing NW Indiana. Results of this work and its impact on student learning in CHEM 121 are described.Pre/post #9Pre/Post #2Figure 2. Qualitative test resultsFigure 3. Vacuum filtration apparatusCo2+(aq) + H2PO41-(aq)  Co(H2PO4)2(s)          eq. 1Co2+(aq) + HPO42-(aq)  CoHPO4(s)                    eq. 23 Co2+(aq) + 2PO43-(aq)  Co3(PO4)2(s)            eq. 3Test tubeVolume of 0.3 M CoCl2(mL)Volume of 0.3 M Phosphate (mL)0 0.0 7.01 1.0 6.02 2.0 5.03 3.0 4.04 4.0 3.05 5.0 2.06 6.0 1.07 7.0 0.0Table 1. Reactant amountsExperimental methods:• Applying the method of continuous variation to determine the identity of an unknown phosphate, a set of eight precipitation reactions was performed by mixing varying concentrations of cobalt and phosphate ion reactants according to Table 1• Quantitative Precipitate (ppt.) Analysis: Each precipitate was separated from the mixture by centrifugation and dried. Experimental ppt. masses were plotted as a function of reactant mole fraction to identify the limiting reactant• Qualitative Supernatant Analysis: Each supernatant was tested qualitatively via observation of supernatant color and reactivity with Fe(NO3)3 to determine the excess reactant Figure 1. Average Mass of Cobalt (II) Phosphate vs. Mole Fraction of Co2+Experimental methods:• Soil samples were collected both upstream (A) and downstream (B) from a local wastewater treatment plant and dried• Microplastics/microfibers were separated from bulk soil according to their a) size using sieves and b) density by suspending them in a ZnCl2 solution (1.3 g/mL) • Low density materials were filtered using vacuum filtration and analyzed with a microscope• Microplastics were further purified by removing natural materials using the Fenton reaction: Fe2+ + H2O2  Fe3+ + HO. + OH-Fe3+ + H2O2  Fe2+ + HOO. + H+• Final analysis of samples was performed using microscopy after the Fenton reaction solution was vacuum filteredResults• My work: Successfully adapted 3-week CHEM 111 experiment to be performed in CHEM 121 during 2 weeks • Student results: Students gained experience performing research and were specifically able to identify microfibers and microplastics in soil samples• Post-lab surveys: Students showed a modest positive shift regarding how they think research is performed and how it should be conducted and interpreted• Post-lab surveys: Students indicated increased awareness about microplastic pollution and why it should be studied/monitoredResults• My work: Developed 3 total methods of analysis (2 qualitative, 1 quantitative) that reliably allowed determination of unknown phosphate• Student results: All students were able to correctly identify unknown based on each of the three methods• Post-lab question observations: Students expressed a range of opinions on whether qualitative or quantitative analysis provides more compelling evidence when identifying their unknown Figure 4. Results of selected survey questions. Question 2 (left) and 9 (middle) were pre/post questions pertaining to scientific process; the right panel shows student opinion on microplastics research. (2) “I have a good understanding of how scientific research is performed in the real world.“(9) “Research is about collecting data which backs your argument.”

Enhancing General Chemistry Labs to Construct Engaging, Colorful Experiments

ValpoScholar

Valparaiso University
ValpoScholar
Symposium on Undergraduate Research and
Creative Expression (SOURCE) Office of Sponsored and Undergraduate Research
Spring 5-3-2018
Enhancing General Chemistry Labs to Construct
Engaging, Colorful Experiments
Emily Statza
emily.statza@valpo.edu
Robert Clark
Valparaiso University, robert.clark@valpo.edu
Laura Rowe
Valparaiso University, laura.rowe@valpo.edu
Julie Peller
Valparaiso University, julie.peller@valpo.edu
Follow this and additional works at: https://scholar.valpo.edu/cus
This Poster Presentation is brought to you for free and open access by the Office of Sponsored and Undergraduate Research at ValpoScholar. It has been
accepted for inclusion in Symposium on Undergraduate Research and Creative Expression (SOURCE) by an authorized administrator of ValpoScholar.
For more information, please contact a ValpoScholar staff member at scholar@valpo.edu.
Recommended Citation
Statza, Emily; Clark, Robert; Rowe, Laura; and Peller, Julie, "Enhancing General Chemistry Labs to Construct Engaging, Colorful
Experiments" (2018). Symposium on Undergraduate Research and Creative Expression (SOURCE). 690.
https://scholar.valpo.edu/cus/690
Limiting Reagent in Action:
Enhancing General Chemistry Labs to Construct Engaging, Colorful Experiments
Emily Statza, Dr. Clark, Dr. Peller, and Dr. Rowe
Valparaiso University
Analysis of Microplastic Pollution in Local Soil: 
Overarching Goal: Provide students with captivating laboratory experiments to solidify lecture material and connect their studies to real-world issues.    
Discussion: 
Limiting Reagent:
• Students gained a more complete understanding of 
limiting reactant stoichiometry
• Multiple analysis modes provided students with 
several complementary approaches to solve a 
chemical problem
• Experiment was more visually appealing by 
employing a transition metal that formed colorful 
compounds
• Future Work: More fully investigate student 
conceptions about what constitutes compelling 
evidence 
Microplastic Pollution:
• Students gained experience applying their 
classroom learning to perform experiments that 
address real-world issues
• Students had a somewhat better perspective on 
how the research process works and what it means
• Future Work: Increase student engagement by 
having students supply their own soil samples and 
hypothesize and present their results
Abstract:
General Chemistry I (CHEM 121) sets the foundation 
for the chemistry education of Valparaiso students; 
therefore, it is critical that the CHEM 121 lecture and 
laboratory courses provide rich learning experiences 
that are meaningful, focused, and engaging. In this 
project, two new or significantly revised laboratory 
experiments were incorporated into the curriculum 
during the Spring 2018 semester: 1) The Limiting 
Reagent in Action: Determining the Formula of a 
Precipitate and 2) The Analysis of Microplastic 
Pollution in Local Soil. The common goals of both labs 
were to increase student understanding of 
challenging general chemistry concepts by enhancing 
student engagement. For Experiment 1, this was 
accomplished by adding additional qualitative testing 
to study the reactions; in the case of Experiment 2, 
this was accomplished by directly connecting course 
material to study real-world pollution problems 
facing NW Indiana. Results of this work and its impact 
on student learning in CHEM 121 are described.
Pre/post #9Pre/Post #2
Figure 2. Qualitative test results
Figure 3. 
Vacuum 
filtration 
apparatus
Co2+(aq) + H2PO4
1-
(aq)  Co(H2PO4)2(s)          eq. 1
Co2+(aq) + HPO4
2-
(aq)  CoHPO4(s)                    eq. 2
3 Co2+(aq) + 2PO4
3-
(aq)  Co3(PO4)2(s)            eq. 3
Test 
tube
Volume of 
0.3 M 
CoCl2
(mL)
Volume of 
0.3 M 
Phosphate 
(mL)
0 0.0 7.0
1 1.0 6.0
2 2.0 5.0
3 3.0 4.0
4 4.0 3.0
5 5.0 2.0
6 6.0 1.0
7 7.0 0.0
Table 1. Reactant amounts
Experimental methods:
• Applying the method of continuous variation to determine the identity of an 
unknown phosphate, a set of eight precipitation reactions was performed by mixing 
varying concentrations of cobalt and phosphate ion reactants according to Table 1
• Quantitative Precipitate (ppt.) Analysis: Each precipitate was separated from the 
mixture by centrifugation and dried. Experimental ppt. masses were plotted as a 
function of reactant mole fraction to identify the limiting reactant
• Qualitative Supernatant Analysis: Each supernatant was tested qualitatively via 
observation of supernatant color and reactivity with Fe(NO3)3 to determine the 
excess reactant Figure 1. Average Mass of 
Cobalt (II) Phosphate vs. 
Mole Fraction of Co2+
Experimental methods:
• Soil samples were collected both upstream (A) and downstream 
(B) from a local wastewater treatment plant and dried
• Microplastics/microfibers were separated from bulk soil 
according to their a) size using sieves and b) density by 
suspending them in a ZnCl2 solution (1.3 g/mL) 
• Low density materials were filtered using vacuum filtration and 
analyzed with a microscope
• Microplastics were further purified by removing natural 
materials using the Fenton reaction: 
Fe2+ + H2O2  Fe
3+ + HO. + OH-
Fe3+ + H2O2  Fe
2+ + HOO. + H+
• Final analysis of samples was performed using microscopy after 
the Fenton reaction solution was vacuum filtered
Results
• My work: Successfully adapted 3-week CHEM 111 experiment to be performed in CHEM 121 during 2 weeks 
• Student results: Students gained experience performing research and were specifically able to identify 
microfibers and microplastics in soil samples
• Post-lab surveys: Students showed a modest positive shift regarding how they think research is performed 
and how it should be conducted and interpreted
• Post-lab surveys: Students indicated increased awareness about microplastic pollution and why it should be 
studied/monitored
Results
• My work: Developed 3 total methods of analysis (2 qualitative, 1 quantitative) that 
reliably allowed determination of unknown phosphate
• Student results: All students were able to correctly identify unknown based on each of 
the three methods
• Post-lab question observations: Students expressed a range of opinions on whether 
qualitative or quantitative analysis provides more compelling evidence when identifying 
their unknown 
Figure 4. Results of selected survey questions. Question 2 (left) and 9 (middle) were pre/post questions 
pertaining to scientific process; the right panel shows student opinion on microplastics research. 
(2) “I have a good understanding of how scientific research is performed in the real world.“
(9) “Research is about collecting data which backs your argument.”


https://scholar.valpo.edu/cgi/viewcontent.cgi?article=1756&amp;context=cus

Enhancing General Chemistry Labs to Construct Engaging, Colorful Experiments

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