Semester Of Organic Chemistry Research Articles

Assessment of Students’ Study Approaches in the First Semester of Organic Chemistry: Patterns of Evolution Diverge According to Students’ Achievement Level

Assessment of Students’ Study Approaches in the First Semester of Organic Chemistry: Patterns of Evolution Diverge According to Students’ Achievement Level

Gas Chromatography–Mass Spectrometric Analysis of Derivatives of Dibenzalacetone Aldol Products

The aldol condensation reaction is one of the many synthesis reactions carried out in second semester organic chemistry laboratories. This reaction was integrated into a novel experiment requiring students to synthesize dibenzalacetone derivatives using the crossed-aldol condensation by reacting different types of benzaldehyde derivatives with acetone, followed by analyzing those products using spectrometric and spectroscopic methods, especially gas chromatography–mass spectrometry (GC–MS). The main objective of this 2 week lab experiment compared to other procedures in the literature was the analysis of the final aldol product using GC–MS methods rather than solely nuclear magnetic resonance (NMR) spectroscopic methods. During the first week’s 3 h laboratory period, students completed the reaction with a known benzaldehyde derivative and acetone to synthesize their aldol product. In the second week, students calculated the percent yield of their product, determined the product’s melting point range, and analyzed the product by thin-layer chromatography, NMR, and GC–MS methods. Students also strengthened their skills of spectral interpretation using NMR spectroscopy, especially distortionless enhancement by polarization transfer NMR, an NMR technique rarely covered in undergraduate organic laboratory sections. Students spent more classroom time during week two, analyzing GC–MS data. Students were shown how to use molecular model kits to understand the fragmentation of compounds in the mass spectrum. As a result, the students who performed this experiment increased their general knowledge of GC–MS spectrometric techniques, including identification of compounds based on their fragmentation pattern.

Hands-On Laboratory Experience Using Adhesives for Remote Learning of Polymer Chemistry

Teaching chemistry without access to a traditional laboratory space is an ongoing challenge that has become especially relevant because of the SARS-CoV-2 pandemic. While several remote learning options exist for covering general chemistry concepts (including kitchen-based experiments, online modules, and virtual reality), few options provide opportunities for hands-on learning about the chemistry of synthetic polymer materials. Here, we offer remote learning modules that use household adhesives as a platform for teaching polymer chemistry outside of the laboratory. These modules are designed for students who have taken at least one semester of organic chemistry and have varied hands-on time commitments, ranging from 2 to 10 total hours each. Concepts covered include polymer synthesis, intermolecular interactions, thermomechanical properties, structure–function relationships, and molecular design. The experiments described in these modules also give students a chance to practice research-relevant skills such as searching for primary literature sources, fabricating test samples, explaining unexpected experimental results, and revising experimental procedures to improve methodologies. Ultimately, these modules provide educators with an additional tool for teaching experimental chemistry outside of the laboratory.

Using Donor–Acceptor Stenhouse Adducts to Teach Photochromism in the Undergraduate Laboratory

There has been dramatic growth in interest and research regarding organic photochromism in recent decades. Despite this, the topic is seldom addressed in the undergraduate chemistry curriculum. Herein, we present a straightforward and robust experiment for the second semester organic chemistry laboratory curriculum which combines multistep synthesis, photochromism, and optical characterization. Over the course of a three-step synthesis, students prepare both the open and closed isomers of a Donor–acceptor Stenhouse adduct. At each stage of the synthesis, the pure products are isolated by filtration and characterized by traditional means (FTIR, 1H NMR). Additionally, students collect UV–vis data on the photoisomerization process and use this to calculate kinetic parameters. An inquiry-based variant of the experiment is also presented.

The process of attrition in pre-medical studies: A large-scale analysis across 102 schools.

The important but difficult choice of vocational trajectory often takes place in college, beginning with majoring in a subject and taking relevant coursework. Of all possible disciplines, pre-medical studies are often not a formally defined major but pursued by a substantial proportion of the college population. Understanding students' experiences with pre-med coursework is valuable and understudied, as most research on medical education focuses on the later medical school and residency. We examined the pattern and predictors of attrition at various milestones along the pre-med coursework track during college. Using a College Board dataset, we analyzed a sample of 15,442 students spanning 102 institutions who began their post-secondary education in years between 2006 and 2009. We examined whether students fulfilled the required coursework to remain eligible for medical schools at several milestones: 1) one semester of general chemistry, biology, physics, 2) two semesters of general chemistry, biology, physics, 3) one semester of organic chemistry, and 4) either the second semester of organic chemistry or one semester of biochemistry, and predictors of persistence at each milestone. Only 16.5% of students who intended to major in pre-med graduate college with the required coursework for medical schools. Attrition rates are highest initially but drop as students take more advanced courses. Predictors of persistence include academic preparedness before college (e.g., SAT scores, high school GPA) and college performance (e.g., grades in pre-med courses). Students who perform better academically both in high school and in college courses are more likely to remain eligible for medical school.

Career Ladder: Luis Alvarez

1990s Early interest in chemistry Luis Alvarez had two semesters of organic chemistry under his belt before he left high school, thanks to an unusual program at his Hollywood, Florida, school. The ...

Exploring Student Thinking about Addition Reactions

Organic chemistry is a required course sequence for many STEM students. However, research indicates that organic chemistry reaction mechanisms are especially challenging for students due to a mixture of underlying conceptual difficulties, the process-oriented thinking inherent to the discipline, and the representations commonly used to depict mechanisms. While student reasoning about many of the reaction types covered in the organic chemistry curriculum has been studied previously, there is minimal research focused specifically on how students think about the mechanisms of addition reactions. Understanding students’ conceptions about addition reactions is valuable for both instructors and researchers, as these reactions are among the first for which students must consider different chemical properties to make a decision about alternate reaction pathways. This study provides insight into how students think about these reactions by probing first semester organic chemistry students’ thinking using think-aloud interviews as they worked through two addition reactions. To elicit a range of thinking, students worked through the mechanisms using either paper and pencil or an app that dynamically represents the molecules. Generally, students were able to identify the steps of the two addition reactions but did not always successfully apply chemical thinking during the mechanistic steps. Most prominently, both groups of students struggled with the concepts related to carbocation stability, frequently misapplying stabilization via substitution and demonstrating difficulty in identifying the potential for resonance stabilization. Our results suggest that instructors should emphasize the conceptual grounding that directs mechanistic steps, in particular when determining carbocation stability. More generally, our findings suggest that instructors must emphasize the skill of considering and weighing different chemical properties when making decisions about alternative reaction pathways.

Homing in on the Capabilities That Are Most Predictive of Student Success in the First Semester of Organic Chemistry

The non-major’s two-semester organic chemistry course at UPR-RP aims at developing a more integrated and meaningful understanding of the fundamentals of Organic Chemistry. To achieve this goal, we ...

Arrows on the Page Are Not a Good Gauge: Evidence for the Importance of Causal Mechanistic Explanations about Nucleophilic Substitution in Organic Chemistry

This three-year study builds on prior work analyzing students’ causal mechanistic explanations about acid–base reactions. Here we extend that work to characterize and investigate how students construct causal mechanistic explanations of simple nucleophilic substitution reactions. After an initial pilot study, we adopted a modified version of the original task prompt which was used in two subsequent years to compare responses from students enrolled in a transformed organic chemistry course (Organic Chemistry, Life, the Universe and Everything) and a traditional organic chemistry course. Student responses were sampled in the middle of the first semester organic chemistry, just after they had learned the material, and once again at the end of the course, to identify how responses changed over time. Our findings from this study include (1) eliciting causal mechanistic explanations requires careful scaffolding to activate productive elements of a response, and (2) students from a transformed course are more likely to construct a causal mechanistic explanation at the end of Organic Chemistry 2 than students from the control group, suggesting that if students are to retain the use of valuable knowledge, this must be supported by instruction and course expectations.

What students write about when students write about mechanisms: analysis of features present in students’ written descriptions of an organic reaction mechanism

Learning to reason through organic reaction mechanisms is challenging for students because of the volume of reactions covered in introductory organic chemistry and the complexity of conceptual knowledge and reasoning skills required to develop meaningful understanding. However, understanding reaction mechanisms is valuable for students because they are useful for predicting and explaining reaction outcomes. To identify the features students find pertinent when explaining reaction mechanisms, we have collected students’ written descriptions of an acid-catalysed amide hydrolysis reaction. Students’ writing was produced during the implementation of Writing-to-Learn assignments in a second semester organic chemistry laboratory course. We analysed students’ written responses using an analytical framework for recognizing students’ mechanistic reasoning, originally developed with attention to the philosophy of science literature. The analysis sought to identify the presence of specific features necessary for mechanistic reasoning belonging to four broad categories: (1) describing an overview of the reaction, (2) detailing the setup conditions required for the mechanism to occur, (3) describing the changes that take place over the course of the mechanism, and (4) identifying the properties of reacting species. This work provides a qualitative description of the variety of ways in which students included these features necessary for mechanistic reasoning in their writing. We additionally analysed instances of co-occurrence for these features in students’ writing to make inferences about students’ mechanistic reasoning, defined here as the use of chemical properties to justify how electrons, atoms, and molecules are reorganized over the course of a reaction. Feature co-occurrences were quantified using the lift metric to measure the degree of their mutual dependence. The quantitative lift results provide empirical support for the hierarchical nature of students’ mechanistic descriptions and indicate the variation in students’ descriptions of mechanistic change in conjunction with appeals to chemistry concepts. This research applies a framework for identifying the features present in students’ written mechanistic descriptions, and illustrates the use of an association metric to make inferences about students’ mechanistic reasoning. The findings reveal the capacity of implementing and analysing writing to make inferences about students’ mechanistic reasoning.

Integrating biochemistry into a program serving multiple tracks in medical laboratory science

This Education Case Study addresses two issues: the program-identified need for more biochemistry content in the pre-requisite course, Organic Chemistry I, and its availability to the Medical Laboratory Science Online Career Ladder track students. The underlying principles for resolving the issues are the constraints of the program curriculum and the unavailability of an online organic chemistry course at Georgia Southern University. The first step in addressing the issues involved collaboration between the Medical Laboratory Science and Chemistry faculty members to identify the specific biochemistry topics on which program courses build. Since the Biochemistry I course has the pre-requisites of two semesters of Organic Chemistry and the medical laboratory program of study only had room for one course in this area, a new course was designed to address the program-identified content need. The new course was offered in a face-to-face format but one of the program tracks utilizes entirely online instruction. To allow those students access to the new course, the course instructor obtained e-Faculty status and undertook designing an online version. The process included the expertise of an instructional designer and the resulting online course was rich in content and teaching strategies to provide the social presence necessary for student engagement in that venue. The online course immediately earned Quality Matters Certification and has been offered three times to date. Forty-one students have taken the new course. Of those eligible to apply, 71% entered the Medical Laboratory Science program and 78% of the entrants have graduated or are on track to do so. The average course GPA data for the 5 cohorts reveals that the strong level of student success in the face-to-face course has not been observed in the online course (3.55 and 2.53, respectively) requiring continued efforts to deliver content, engage students, and assess learning in alternative ways.

Utilizing Rasch analysis to establish the psychometric properties of a concept inventory on concepts important for developing proficiency in organic reaction mechanisms

Abstract Undergraduate organic chemistry has been found to be historically difficult for students and one area where students struggle is organic reaction mechanisms. The difficulties students face with reaction mechanisms has been a source of interest in chemical education research but most studies done have been purely qualitative. An assessment tool that could be used on a large-scale for instructors to gauge the difficulties their students face, would be useful. The aim of this pilot study is to use Rasch analysis to establish the validity and reliability of the concepts important for developing proficiency in organic reaction mechanisms inventory (RMCPI). The test, containing 25 items, was administered to first semester organic chemistry students (N = 44) at a mid-sized university. The data was analyzed using Rasch techniques to explore the dimensionality of the instrument, the difficulty of the items, the item fit, and the reliability. The results indicate that the instrument is unidimensional and most of the items fit well to the dichotomous Rasch model. The test was found to be difficult and this will be explored further by increasing the sample size, administering the test to students from other universities and increasing the number of items on the inventory.

Integrating Biochemistry Into a Program Serving Multiple Tracks in Medical Laboratory Science

<h3>ABSTRACT</h3> This education case study addresses 2 issues: the program-identified need for more biochemistry content in the prerequisite course, Organic Chemistry I, and its availability to the Medical Laboratory Science Online Career Ladder track students. The underlying principles for resolving the issues are the constraints of the program curriculum and the unavailability of an online organic chemistry course at Georgia Southern University. The first step in addressing the issues involved collaboration between the Medical Laboratory Science and Chemistry faculty members to identify the specific biochemistry topics on which program courses build. Because the Biochemistry I course has the prerequisites of 2 semesters of Organic Chemistry and the medical laboratory program of study only had room for 1 course in this area, a new course was designed to address the program-identified content need. The new course was offered in a face-to-face format, but one of the program tracks utilizes entirely online instruction. To allow those students access to the new course, the course instructor obtained e-Faculty status and undertook designing an online version. The process included the expertise of an instructional designer, and the resulting online course was rich in content and teaching strategies to provide the social presence necessary for student engagement in that venue. The online course immediately earned Quality Matters Certification and has been offered 3 times to date. Forty-one students have taken the new course. Of those eligible to apply, 71% entered the Medical Laboratory Science program, and 78% of the entrants have graduated or are on track to do so. The average course grade point average data for the 5 cohorts reveal that the strong level of student success in the face-to-face course has not been observed in the online course (3.55 and 2.53, respectively), requiring continued efforts to deliver content, engage students, and assess learning in alternative ways.

Patching a leak in an R1 university gateway STEM course.

A cognitively intensive companion service course has been introduced to the main fall general chemistry class at Cornell University. For years 2015 and 2016, priority students (those from groups under-represented and economically disadvantaged) show respectively improvement of +0.67 and +0.51 standard deviations in final course grade compared to priority students not in the program. Non-priority students show respectively a +0.66 and +0.62 standard deviation improvement. Progressive improvement (as measured by higher than expected Final Exam scores than what would have been expected solely from a given student’s earlier Exam 1 score) demonstrates conclusively the service course’s role in the enhanced outcomes. Progressive retention (as measured by the following year fall semester’s organic chemistry exam scores compared to what would have been expected based on a given student’s general chemistry final exam score) demonstrates that, on the average, the earlier observed progressive improvement is significantly retained in a chemistry course one year later. Preliminary retention statistics suggest a significant increase in first year to second year retention. A meta analysis of results from previously reported chemistry service courses indicate that such performance gains are difficult to achieve and hence common elements of the few effective programs may be of high value to the STEM education community.

An inquiry-based exercise in medicinal chemistry: Synthesis of a molecular library and screening for potential antimalarial and anti-inflammatory compounds.

The development of new medicines holds particular fascination for chemistry, biochemistry, and biology students interested in a career in medicine or the life sciences. The identification and refinement of lead compounds to treat diseases requires researchers to be facile in a number of different disciplines including organic synthesis, biochemistry, cell biology, and molecular biology. We have developed an interdisciplinary, inquiry-based laboratory spanning both organic chemistry and biochemistry classes that acquaints students with research in medicinal chemistry. The first part of the exercise takes place in the second semester of organic chemistry, where pairs of students design and execute their own multistep synthesis of a novel compound with anti-inflammatory and/or antimalarial potential. Later, in first semester biochemistry, many of the same students then test these synthesized compounds for cytotoxicity, inhibition of the enzyme nitric oxide synthase, and inhibition of the transcription factor NF-kB. Learning outcomes, measured by the Classroom Undergraduate Research Experience (CURE) survey, suggest that students participating in both classes had higher gains than an average student. © 2018 International Union of Biochemistry and Molecular Biology, 46(5):424-434, 2018.

Analysis of Assessment on Biochemistry Threshold and Core Concepts in Students with Varying Chemistry Backgrounds

Stockton University is one of a few number of universities that do not follow the traditional introductory Chemistry sequence. Instead of the usual year of General Chemistry followed by one year of Organic Chemistry, Stockton follows a 1:2:1 one model of one semester of General, two semesters of Organic Chemistry followed by one of General. The prerequisite for students to take Biochemistry at Stockton is the first two semesters of Chemistry or one semester of General and one of Organic. About half of the students take Biochemistry with these prerequisites while the other half have various combinations of Chemistry courses. Previous assessments have shown there is a stronger correlation between the students grade in Biochemistry compared to previous Chemistry courses rather than the number of Chemistry courses. An assessment was developed to test the level of knowledge on three threshold concepts for incoming Biochemistry students: biochemical pathways, physical basis of interactions and free energy. A fourth component was added based on functional groups and organic chemical reactions. Students were given the assessment on the first day of class as well as at the end of the term. To insure that the students took the assessment seriously, extra credit (2% of final grade) was offered for a high enough score on each test. For the analysis of results, the exam questions were divided into categories based on the threshold concept and average scores were calculated for students based on the chemistry background. Grades less than 50% were described as lacking an understanding of the topic, grades between 50 and 70% were described as having a basic understanding of the topic and grades greater than 70% were having a deep understanding of the topic. While there were differences in other threshold concepts between the groups, all students were lacking in the free energy question at the start and end of the semester and showed the smallest improvements.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Testing a reciprocal causation model between anxiety, enjoyment and academic performance in postsecondary organic chemistry

Affective factors such as the achievement emotions are considered critical for students’ academic performance in STEM degree programmes and careers. In this study, a reciprocal causation model was tested between two affective factors: enjoyment and anxiety, and organic chemistry course performance. Each variable was measured three times in four sections of a first semester organic chemistry course. This study investigates a reciprocal causation relationship between anxiety, enjoyment and achievement as measured by exam performance compared to unidirectional structures of performance and affect relationships. Results show that the reciprocal causation model with an exam snowballing effect best fits data among the alternative models. There is a small and significant negative relationship between anxiety and performance contrasted with a positive relationship between enjoyment and performance throughout the semester. The evidence of the reciprocal relationship between anxiety, enjoyment and achievement indicates that instructors of organic chemistry can work to eliminate factors associated with low performance. Gathering information regarding anxiety and enjoyment along with performance can inform educators about the emotional state of their classrooms. Future research should consider achievement emotions in light of educational reforms to ensure that innovative curricula or pedagogies are functioning in the classroom as intended.

Analysing the impact of a discussion-oriented curriculum on first-year general chemistry students' conceptions of relative acidity

Instructional strategies that support meaningful student learning of complex chemical topics are an important aspect of improving chemistry education. Adequately assessing the success of these approaches can be supported with the use of aligned instruments with established psychometrics. Here, we report the implementation and assessment of one such curriculum,Chemical Thinking, on first-year general chemistry students' conceptions of relative acidity using the recently-developed concept inventory,ACIDI. Our results reveal that, overall, students performed significantly better onACIDIfollowing instruction, with scores consistent with those previously reported for students who had completed one semester of organic chemistry. Students performed equally well on a delayed post-test administered ten weeks after final instruction, which suggests that instruction promoted a stable conceptual reprioritisation. Item analysis ofACIDIrevealed that students generally made conceptual gains on items where inductive effects were the primary determinants of conjugate base stability and relative acidity. However, students overwhelmingly struggled on items where resonance was the primary determinant. Analysis of student–student arguments in active learning settings provided evidence for how the quality of student arguments impacted their conceptions. Overall, these findings suggest that students were able to avoid several superficial misconceptions cited in the literature about relative acidity, and that this topic, traditionally taught exclusively in organic chemistry, may be introduced earlier in the sequence of curricular topics. Implications for future studies on the role of argumentational aspects of student–student conversations and facilitation strategies in promoting or hindering meaningful learning are discussed.

Career Ladder: Warren Samms

1990s Early experimentation While his peers in Wichita, Kan., were making a mess with baking soda volcanoes, Warren Samms (right) favored a cabbage acid/base indicator for his elementary science fair experiment. “At the time, it felt like being an actual scientist rather than playing with a neat toy.” 1999 Organic or bust Samms stayed in Wichita for college, majoring in chemistry and biology at Friends University. “When I got to my second semester of organic chemistry, I had a problem,” he says. “Jazz band practice met at the same time as organic chemistry.” Supported by a trumpet scholarship, Samms was forced to choose between music and chemistry until organic professor Kathryn Boyle (left) intervened. Boyle told Samms she would take him on for a one-on-one independent study. “She’s the reason I stuck with chemistry,” Samms says. 2003 Hooked on drug testing During graduate school at Wichita State University, Samms researched

Probing the question order effect while developing a chemistry concept inventory

The design of assessment tools is critical to accurately evaluate students' understanding of chemistry. Although extensive research has been conducted on various aspects of assessment tool design, few studies in chemistry have focused on the impact of the order in which questions are presented to students on the measurement of students' understanding and students' performance. This potential impact has been labeled the question order effect in other literature and may be considered as a threat to the construct validity of the assessment tool. The set of studies described in this article tested whether question order effects were present within a concept inventory on acid-based chemistry. In particular, we tested whether the order of two conceptually isomorphic questions, one pictorial and one verbal, affected students' performance on the concept inventory. Two different versions of the inventory were developed and collected from students enrolled in the second semester of first-year university chemistry courses (general chemistry;N= 774) at two different institutions and to students enrolled in the first semester of organic chemistry (N= 163) at one of the two institutions. Students were further divided in two groups based on their self-reported level of effort in answering the concept inventory. Interviews were also conducted with a total of 19 students at various stages of the studies. Analyses of differences in students' responses to the two versions of the inventory revealed no question order effect in all settings. Implications for instructors and researchers are provided.