Journal of Chemical Education最新文献

{"title":"Quantum Dots Synthesis and Application in a Course-Based Undergraduate Research Experience","authors":"Mayara Fontanelli dos Santos,&nbsp;Ana Luiza de Camargo Doimo,&nbsp;Numbia Aparecida Lima,&nbsp;Josenilton de Jesus dos Santos,&nbsp;Marcos V. Palmeira-Mello and Caterina G. C. Marques Netto*,&nbsp;","doi":"10.1021/acs.jchemed.4c0086910.1021/acs.jchemed.4c00869","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00869https://doi.org/10.1021/acs.jchemed.4c00869","url":null,"abstract":"<p >The course-based undergraduate research experiences (CURE) approach is increasingly being used in undergraduate experimental courses. Here, we describe the implementation of CURE in an upper-level inorganic chemistry course, in which students were assigned different current themes to study. This paper focuses on the theme of quantum dots, highlighting how guidance, inquiry, and research were integrated into the classroom. The quantum dots theme introduced various concepts to students such as electron–hole pairs, band gaps, particle capping, doping, and size effects. A questionnaire distributed among the students revealed that the continuation of their research throughout the semester kept them engaged, and they maintained a high level of interest in the subject. The success of CURE in this course is revealed, as the instructor and professor will maintain this approach in the next semesters.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5476–5483 5476–5483"},"PeriodicalIF":2.5,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.jchemed.4c00869","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142850371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nuclear Magnetic Resonance-Based Method to Teach the “Effect of Substituents on the Reactivity and Orientation” of Aromatic Compounds","authors":"Chao-Tun Cao,&nbsp; and ,&nbsp;Chenzhong Cao*,&nbsp;","doi":"10.1021/acs.jchemed.4c0083210.1021/acs.jchemed.4c00832","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00832https://doi.org/10.1021/acs.jchemed.4c00832","url":null,"abstract":"<p >The effect of substituents on the reactivity and orientation is important for aromatic compounds in organic chemistry. The “telling style” is used in traditional teaching methods and does not make a deep impression of the learned content in students. The lack of a clear criterion causes a vague understanding of the orientation of the substituted groups. This study developed a new method termed the “nuclear magnetic resonance (NMR)-based method (NBM)” to teach the “effect of substituents on reactivity and orientation”, which changed the “telling style” teaching method to a “discussing style” teaching method. A normalized method was used to correct the scale of ¹H NMR chemical shift change to that of ¹³C NMR chemical shift change. The sum of the ¹H and ¹³C NMR chemical shift changes was used to discuss the following issues: (i) verifying the activating or deactivating groups, (ii) determining the <i>ortho–para</i> or <i>meta</i> directors, and (iii) predicting the orientation of an incoming group in disubstituted benzene. The NBM presented in this paper is intuitive and simple, which can help students to understand the “effect of substituents on reactivity and orientation” in electrophilic aromatic substitution and cultivate the ability of students to analyze problems using NMR.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5306–5312 5306–5312"},"PeriodicalIF":2.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Introducing High School Students to the Amount of Substance, the Mole, and Avogadro’s Number Through a Hands-On Guided Inquiry Activity Using 3-D Geometrically Shaped Samples of Elements and Cubes Made of LEGO Bricks","authors":"Derek Mainus,&nbsp; and ,&nbsp;Thomas H. Bindel*,&nbsp;","doi":"10.1021/acs.jchemed.4c0101110.1021/acs.jchemed.4c01011","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c01011https://doi.org/10.1021/acs.jchemed.4c01011","url":null,"abstract":"<p >An activity is presented in which students discover how to count atoms through measurement. Students make measurements on a variety of chemical elements in the shapes of geometric solids. From these measurements and the method of counting atoms, students determine a number-of-atoms data set, which consists of an Avogadro’s number for each chemical element in the set. The data set is used to introduce students to Avogadro’s number, the quantity of the amount of substance, and the respective SI unit, the mole.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5540–5546 5540–5546"},"PeriodicalIF":2.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Interplay of Hydration and Hydrolysis upon the Keto–Enol Tautomerism of β-Diketones","authors":"Chengyang Zhang,&nbsp;Guoyang Zhang,&nbsp;Hongcen Zheng and Shujuan Zhang*,&nbsp;","doi":"10.1021/acs.jchemed.4c0079510.1021/acs.jchemed.4c00795","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00795https://doi.org/10.1021/acs.jchemed.4c00795","url":null,"abstract":"<p >This study seeks to elucidate the fundamental principles underlying the hydration, hydrolysis, and enolization of β-diketones, aiming to enhance students’ comprehension of the link between fundamental chemical principles and the practical implications of keto–enol tautomerization and diketone-gem diol equilibrium in diverse chemical reactions. The research explores the hydration and hydrolysis kinetics of β-diketones using NMR and UV spectroscopy as well as the substituent effects on these kinetics and their influence on enolization. The insights gained from this study are valuable for students of chemistry, particularly those with an interest in the fundamental aspects of physical chemistry and the environmental aspects of organic chemistry. By establishing a clear link between theoretical insights and practical applications, this research contributes to the advancement of chemical education and provides students with a deeper understanding of the underlying chemical processes in real-world contexts.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5460–5467 5460–5467"},"PeriodicalIF":2.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Weekly Cumulative Quizzes in Organic Chemistry","authors":"Maarten T. P. Beerepoot*,&nbsp;J. Aleksi Kosonen and Marius Haugland-Grange,&nbsp;","doi":"10.1021/acs.jchemed.4c0074110.1021/acs.jchemed.4c00741","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00741https://doi.org/10.1021/acs.jchemed.4c00741","url":null,"abstract":"<p >A challenge in organic chemistry as well as in other subjects is that a set of fundamental skills is required to master more advanced topics. In an attempt to force students to invest in learning fundamental concepts before working with more advanced topics, we have introduced weekly compulsory quizzes and associated practice tests in our introductory organic chemistry course. The weekly quizzes are <i>cumulative</i> in the sense that the students are tested on the current <i>and all previous</i> topics in each quiz. The aim of the present work is to motivate, describe, and discuss the implementation of these weekly cumulative quizzes and to gain insight into how their use may benefit student learning in the subject. In particular, we seek to disentangle <i>preference</i> and <i>perceived learning</i> when it comes to students’ perspectives on the cumulative and frequent nature of the quizzes. We analyzed the use of the weekly cumulative quizzes as well as the practice tests and obtained students’ perspectives through evaluation surveys. Usage statistics (from 16 students) indicate that the cumulative quizzes force the students to engage with all previous topics every week, whereas the practice tests that are associated with each topic are mostly used in the week the topic is introduced. Importantly, the students are convinced that the cumulative nature of these quizzes is beneficial to their learning. We document not only a perceived learning benefit (<i>Which do you think is best for your learning?</i>) but also a preference (<i>Which do you like best?</i>) among students for cumulative quizzes vs noncumulative quizzes as well as for weekly quizzes vs quizzes every 2–4 weeks. Despite the low number of students in the present study, weekly cumulative quizzes seem to be a promising tool to build fundamental skills in organic chemistry and other subjects.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5272–5279 5272–5279"},"PeriodicalIF":2.5,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.jchemed.4c00741","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142850290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of Iron(II) in Supplements Using Redox Titration and UV–Visible Spectroscopy","authors":"Rosalynn Quiñones*,&nbsp;Heather Knott,&nbsp;Leslie Frost,&nbsp;Megan Bartram,&nbsp;Trace Clark,&nbsp;Tamara D. Westfall and José A. Buxó,&nbsp;","doi":"10.1021/acs.jchemed.4c0109010.1021/acs.jchemed.4c01090","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c01090https://doi.org/10.1021/acs.jchemed.4c01090","url":null,"abstract":"<p >This study examined a comprehensive approach to quantifying iron in over-the-counter supplements through two laboratory experiments designed for undergraduate students in analytical chemistry and instrumental analysis courses. The experiments employed redox titrations and UV–vis spectroscopy, reinforcing key techniques, such as titration, solution preparation, dilution, glassware handling, and spectroscopic analysis. In the first experiment, students prepared solutions and observed color changes, indicating the complete oxidation of iron II during redox titrations. In the second experiment, students utilized the Beer–Lambert law to construct and analyze an external calibration curve with a UV–vis spectrophotometer, enabling the measurement of iron levels in the supplements. The students performed a statistical analysis to discuss the mean and variance values between the two methods as well as compare their calculated iron amounts with the advertised quantity on product labels. The majority of students did not find a statistically significant difference in the average calculated iron content for the same analyzed brand between the two techniques. The average for the redox experiment was 67.20 ± 11.45 mg, while UV–vis was 63.83 ± 12.38 mg of iron. This experiment was designed to be adaptable and can include various over-the-counter products. Additionally, a method using a lower acid concentration was developed to minimize the use of concentrated acid. Although the experiments can be applied as individual experiments, the combination of both allowed students to reinforce key statistical techniques through a comparison of the two procedures. This comprehensive approach caters to students across different levels of chemistry courses, from introductory to advanced, providing a practical application of theoretical concepts.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5484–5491 5484–5491"},"PeriodicalIF":2.5,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.jchemed.4c01090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142842922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Colloidal Cards: Effects of Game-Based Learning on Student’s Achievements in Colloidal Science","authors":"Elvira Gómez,&nbsp;Carmen Sousa and Albert Serrà*,&nbsp;","doi":"10.1021/acs.jchemed.4c0084710.1021/acs.jchemed.4c00847","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00847https://doi.org/10.1021/acs.jchemed.4c00847","url":null,"abstract":"<p >Educational games garnered significant attention as effective learning tools, blending proven efficiency in improving learning outcomes with engaging and appealing environments that foster peer collaboration. Despite the central role of colloids in chemical applications, colloidal chemistry is often addressed superficially or qualitatively in many university settings, frequently relegated to noncompulsory subjects. Yet, the profound industrial and technological applications of colloidal chemistry, spanning fields like food, biomedicine, and paints, make it one of the most socially and economically impactful branches of chemistry globally. Hence, there is a pressing need to create effective tools that facilitate the teaching of colloidal systems, aiding in the comprehensive understanding of their characteristics and properties. This paper introduces a novel educational game named “Colloidal Cards” designed as an auxiliary tool for teaching and learning colloidal systems. The game aims to achieve three primary objectives: (i) facilitate the identification of everyday and industrial colloidal systems; (ii) impart knowledge on the key physicochemical properties of colloidal systems; and (iii) enhance comprehension of the stability of colloidal systems and the mechanisms to destabilize them.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5313–5323 5313–5323"},"PeriodicalIF":2.5,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.jchemed.4c00847","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142850288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bridging the Gap: Examining Student Engagement in a Hybrid POGIL General Chemistry Class","authors":"Shaghayegh Fateh,&nbsp;Zubeyde Demet Kirbulut Gunes,&nbsp;Aspen Malone,&nbsp;Gabriella Cote,&nbsp;Amy J. Phelps,&nbsp;Ryleigh N. Porter and Gregory T. Rushton*,&nbsp;","doi":"10.1021/acs.jchemed.3c0079110.1021/acs.jchemed.3c00791","DOIUrl":"https://doi.org/10.1021/acs.jchemed.3c00791https://doi.org/10.1021/acs.jchemed.3c00791","url":null,"abstract":"<p >In today’s educational system, distance learning has become a prominent instructional method. Despite its prevalence, concerns linger regarding its efficacy in effectively engaging students. A hybrid class utilizing Process Oriented Guided Inquiry Learning (POGIL) activities was examined, with students participating in person for half of the classes and participating remotely for the other half. The class was arranged such that, on any given day, approximately half of the students attended class in person and the other half joined remotely. Through an analysis of students’ interactions and conversations, the study’s design aimed to gauge the impact of active learning on the same students in two different environments. We observed discourse frequency and key discursive moves in both learning environments which were consistent with the substantive engagement expected in a student-centered experience. Despite all students at times being both in-person and remote learners engaging in group interactions, students demonstrated an overall lower level of engagement in group conversations when participating remotely. These results demonstrated the influence of transactional distance which posits that a psychological and communicative divide exists between students and instructors in distance education. Interviews with the course instructor and select students shed light on potential factors influencing this difference in engagement including increased distractions, reduced accountability, and a perceived lack of community among remote learners. Acknowledging the influence of individual differences such as personality, emotions, and attitude toward the course, the study also identified certain students who deviated from the overall participation patterns. Some learners exhibited heightened engagement in discussions when remote, in contradiction to the overall trend. Implications for supporting student engagement in hybrid learning environments are considered.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5147–5159 5147–5159"},"PeriodicalIF":2.5,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142843014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Biochemistry Teaching Experiment That Demonstrates the Digestion of Carbohydrates, Proteins, and Lipids in the Digestive Tract","authors":"Yonghui An*,&nbsp; and ,&nbsp;Yitian Wang,&nbsp;","doi":"10.1021/acs.jchemed.4c0071410.1021/acs.jchemed.4c00714","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00714https://doi.org/10.1021/acs.jchemed.4c00714","url":null,"abstract":"<p >High school chemistry and biology courses often face challenges in integrating interdisciplinary and complex topics like human digestion, leading to unsatisfactory learning outcomes and diminished student interest. This study introduces a new teaching experiment that simulates the digestive process through hands-on chemical methods, allowing students to visualize biochemical changes and gain a deeper understanding of essential concepts. Structured around the CORE learning cycle (Chemical Observations, Representations, and Experimentation), the experiment guides students through enzyme functions, nutrient breakdown, and the testing of digestive products. This approach is designed to enhance comprehension, encourage inquiry, prompt students to formulate new hypotheses, design experiments, and foster scientific reasoning. By engaging students in active learning, the experiment stimulates curiosity and motivates exploration beyond the standard curriculum.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5437–5443 5437–5443"},"PeriodicalIF":2.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142851146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating Maker Education into the Research Project of Undergraduate Chemistry Program: Low-Cost Arduino-Based 3D Printed Autotitrator","authors":"Kheng Soo Tay*,&nbsp; and ,&nbsp;Jeng Lu Eng,&nbsp;","doi":"10.1021/acs.jchemed.4c0048610.1021/acs.jchemed.4c00486","DOIUrl":"https://doi.org/10.1021/acs.jchemed.4c00486https://doi.org/10.1021/acs.jchemed.4c00486","url":null,"abstract":"<p >This project was designed to incorporate maker education into the final-year research project of the undergraduate chemistry program. It involves taking a project from concept to prototype through project-based learning, emphasizing hands-on learning experiences to solve real-world problems. A final-year undergraduate chemistry student was involved in this work. This student identified a problem through a literature review, designed the necessary equipment, built the prototype to address the identified problem, and assessed its performance using statistical methods. The student successfully developed a low-cost autotitrator using Arduino Uno-compatible microcontrollers, a pH sensor, an open-source PLX-DAQ data acquisition system, 3D printing technology, and various electronic components for determining the percentage of total acidity in fruit juices. Engaging in this project significantly enhanced the student’s technical skills and developed problem-solving abilities, critical thinking, and creativity, which are essential for the future workforce. Additionally, this project enables chemistry students to gain a deeper understanding of the hardware and equipment development process. Moreover, it trains students in utilizing open-source software and identifying cost-effective solutions for building prototypes to solve real-world problems. The concept of this project is adaptable and can be applied to train students in designing and building various chemistry-related equipment.</p>","PeriodicalId":43,"journal":{"name":"Journal of Chemical Education","volume":"101 12","pages":"5430–5436 5430–5436"},"PeriodicalIF":2.5,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142844138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}