Journal of Chemical Education最新文献

A laboratory course on organic chemistryis presented in the contextof isolating and converting natural products for those interestedin developing their laboratory curriculum and activities. The coursefeatures a robust 5-step laboratory synthesis of vanillin from cloves.It was designed at the Department of Chemistry Education at RWTH AachenUniversity and successfully implemented in the Bachelor’s programPharmaceutical Management and Production at DIPLOMA University ofApplied Sciences, where it was evaluated with 12 cohorts and a totalof 112 second-year undergraduate students. The educational approachenables students to conduct the entire experimental process, fromcloves to vanillin, overcoming limitations of an older laboratorysynthesis published in this journal. Steps of the original procedurethat proved too dangerous or unsuccessful were substituted, employingmodern aspects of transition metal catalysis. The synthesis involvesa wide range of typical laboratory operations that serve as learningobjectives, including Soxhlet extraction, the use of rotary evaporators,vacuum distillation, vacuum filtration, crystallization, and puritytesting using refractive index, melting point, and gas and thin-layerchromatography. The course offers opportunities to address basic principlesof organic synthesis, such as retrosynthetic considerations, protectivegroups, or acid/base/transition metal catalysis, in the context ofdaily life natural products, which should increase student motivationand interest in these topics.

English is the primary language ofcommunication and knowledgeexchange in the global scientific community. Therefore, English MediumInstruction (EMI) in undergraduate chemistry education is expectedto provide students with broader access to academic resources andenhance their competitiveness for graduate studies and internationalcareers. However, for non-native English speakers, language barrierscan pose challenges, potentially hindering comprehension and decreasinglearning motivation. In this study, we compared the academic performanceof chemistry major students enrolled in EMI and Chinese Medium Instruction(CMI) programs who followed the same curriculum over three differentenrollment years from 2022 to 2025. We examined students’ learningoutcomes from introductory level courses, General Chemistry and GeneralChemistry Laboratory, two advanced chemistry courses, Organic Chemistryand Physical Chemistry, and a specific topic course, The Applicationof Group Theory in Chemistry. Notably, almost none of the EMI studentshad prior experience with English-based instruction in Chemistry beforeentering university. Despite this, our findings revealed no clearcorrelation between English proficiency and academic performance,and the overall achievement levels of EMI and CMI students were comparableacross most courses. Interestingly, academic performance in entry-levelGeneral Chemistry emerged as a strongly associated factor with subsequentachievement in advanced chemistry courses. However, EMI students’grades exhibited two distinct groups in some courses and a slightlyhigher program dropout rate. Our results also found modern technologiessuch as YouTube videos and ChatGPT play important roles in loweringlanguage barriers. Drawing on Sociocultural Theory, TranslanguagingTheory, and Self-Determination Theory, we interpret these findingsas suggesting that learning in EMI chemistry contexts is supportedby the interaction of mediational resources, translanguaging practices,and learner development. Finally, we discuss pedagogical implicationsand propose instructional strategies to more effectively support EMIstudents in undergraduate chemistry education.

Olefinmetathesis is a fundamental discovery in chemistryand hasbeen introduced as an experiment for undergraduate students in laboratorycourses. As a major progress, olefin cross-metathesis exhibits multipleselectivities, but these selectivities have not been discussed inundergraduate laboratory courses. In this report, we present an inexpensiveolefin metathesis experiment that was designed for undergraduate training.The experiment systematically demonstrates several selectivity issues,including (i) substrate-dependent selectivity, (ii) catalyst-dependentselectivity, and (iii) product stereoselectivity.

The classical structure of physical chemistry laboratorycoursesoften relies on delayed, report-based assessment, which can hinderconceptual understanding and student engagement, particularly in largeclasses. In this study, we report the redesign of an undergraduatephysical chemistry laboratory course aimed at closing the Instruction–Response–Feedback(I–R–F) loop through systematic implementation of continuousand structured feedback mechanisms. The course was offered to twocohorts of approximately 50 students each, one during the daytimeand one during the evening, allowing assessment of both feasibilityand robustness across different class contexts. Key elements includedshort postlaboratory assessments completed during the laboratory session,weekly collective discussion sessions, and guided laboratory reportsstructured as process-oriented guides. Pre- and postcourse self-assessmentsurveys were administered to both cohorts. Statistically significantimprovements were observed in the majority of items surveyed for bothcohorts. The proportion of confident responses increased from 46%to 81% in the daytime cohort and from 36% to 76% in the evening cohort,with both converging to comparable levels by the end of the course.These results demonstrate that scalable closure of the I–R–Floop is feasible in large laboratory classes and is associated withincreased student engagement and perceived learning in experimentalphysical chemistry courses.

Inthe context of the county high school revitalization initiative,this study explores the design and classroom implementation of aninquiry-based chemistry laboratory unit integrating situational contextsand scaffolding instruction to promote laboratory inquiry skills amongstudents in Chinese county-level high schools. Using the theme “TheMysteries of Polyphenols”, everyday materials familiar to students(e.g., tea and purple cabbage) were employed to construct a sequenceof progressively developed real-life situations centered on the structureand properties of phenolic compounds. An inquiry continuum was designedin which instructional scaffolds were systematically faded as studentsmoved through three levels of inquiry: confirmation, structured, andguided inquiry. Students were guided to progressively complete thefull experimental inquiry cycle, including problem interpretation,theoretical analysis, experimental design, implementation, and resultsdiscussion. The study was implemented with a group of grade 11 studentsat a county high school in northeastern China. Students’ developmentin experimental inquiry skills was evaluated through classroom observations,analysis of student worksheets, and cognitive interviews. The teachingeffects suggest that students demonstrated improved ability to connectchemical concepts with real-life contexts, design experimental procedures,and engage in evidence-based reasoning. This teaching design offersan instructive framework for enhancing experimental inquiry skillsand promoting learning interests in high school chemistry classrooms.

Phosphor-converted light-emitting diodes (pc-LEDs) providean effectiveplatform for introducing undergraduate students to luminescent materialsand device fabrication. However, the preparation of conventional phosphorsoften involves harsh conditions or toxic materials, limiting theiruse in teaching laboratories. In this work, we present an undergraduatelaboratory experiment based on lead-free, tin-based zero-dimensional(0D) perovskites as alternative phosphors. Using a simple antisolvent-assistedmethod, students synthesize three 0D tin-based perovskites in powderor single-crystal form and investigate their optical properties. Theas-prepared materials are subsequently integrated with commercial365 nm UV LED chips to fabricate orange-yellow, orange-red, and red-emittingpc-LEDs, providing a direct and visually engaging demonstration ofwavelength conversion. Through this experiment, students gain hands-onexperience in material synthesis, optical characterization, and basicdevice fabrication. The activity highlights the relationship betweenmaterial properties and device performance while introducing conceptsin photophysics, solid-state materials, and sustainable chemistry.This experiment offers an accessible and interdisciplinary approachto connecting fundamental chemistry with modern optoelectronic applications.

Assessing students’ chemical literacy is necessaryfor improvinginstruction. Schools and regional education authorities require aneffective, reliable, and easy-to-use measurement instrument for educationalquality monitoring. This study defined a literacy-oriented chemistryachievement assessment framework and developed an assessment instrumentfor students in grades 9–11. The Rasch model was used to establishempirical evidence for the reliability and validity of the measures.Findings indicate that the instrument meets the requirements of standardizedtests for reliability and validity. The Bookmark Method was used todefine literacy-oriented chemistry achievement levels into excellent,advanced, proficient, and basic. The instrument can be used to assessstudents’ progress in literacy-oriented chemistry achievementfrom middle school to high school, informing regional education policies,accountability, and curriculum and instructional improvement.

Inpharmaceutical formulations, excipients are not inert additivesbut critical determinants of the solid-state properties, dissolutionperformance, and oral bioavailability of active pharmaceutical ingredients(APIs). Therefore, an understanding of the intrinsic mechanisms behindthe interactions between drugs and excipients has become a core fundamentalcompetency for pharmacy undergraduates. Traditional pharmacy curriculaare still predominantly focused on theory with limited practical sessions,which leaves students unable to effectively translate their theoreticalknowledge into practical application. To address this pedagogicalgap, we designed a four-week comprehensive experiment course, includingthe preparation and characterization of particles using mefenamicacid (MA) as an API and three excipients (Poloxamer 188, HPMCAS, andEudragit L100) for pH-driven coprecipitation. The particles were systematicallycharacterized using laser particle size analysis, scanning electronmicroscopy (SEM), powder X-ray diffraction (PXRD), differential scanningcalorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR),and proton nuclear magnetic resonance spectroscopy (¹HNMR). The data analysis elucidated that intermolecular interactionsare the core regulatory mechanism. The assessment results for participatingundergraduate students show that the intended learning objectiveswere fully achieved. The main outcomes included bottom-up particlepreparation, solid-state characterization, and mechanistic analysisof hydrogen bond interactions between drugs and excipients. This experimentseamlessly integrates theory and practice by rational excipient selectionand provides a robust, resource-adaptable teaching module to equipstudents for pharmaceutical R&D careers.

Reactioncalorimetry is an important tool for chemicalprocess-safetyassessment, but conventional research-grade instruments are oftentoo costly and complex for routine undergraduate teaching. This articledescribes a laboratory experiment that uses a bench-scale isothermalheat-flow reaction calorimetry platform to teach quantitative thermal-hazardassessment in chemical safety engineering. Using the neutralizationof acetic acid with sodium hydroxide as a model system, students determinethe heat of reaction (Q_r) and use it to estimate the adiabatic temperature rise (ΔT_ad) and the maximum temperatureof the synthesis reaction (MTSR). Under selectedclassroom operating conditions, the experiment produced a well-definedexothermic peak and reaction-heat values that were in acceptable agreementwith the literature value for the neutralization enthalpy. Among 15student groups formed from 30 third-year undergraduates, 14 groups(93%) successfully completed peak integration and subsequent calculationsof ΔT_ad and MTSR.

The magnetocaloric effect provides a contemporary andexperimentallygrounded context for teaching entropy, heat capacity, Maxwell relations,and phase transitions in upper-division physical chemistry and relatedchemical physics or materials chemistry courses. This Tutorial presentsa modular instructional sequence that guides students from basic thermodynamicrelations to the interpretation of magnetization, heat-capacity, andmagnetic-entropy-change data. The material is designed for flexibleuse as one or two class periods, a homework assignment, or a shortproject module. Students calculate entropy changes from magnetizationand heat-capacity data, compare first- and second-order magnetic transitions,and complete order-of-magnitude estimates involving cooling loads,adiabatic temperature spans, magnetic-field requirements, and materialmass. The Supporting Information provides an instructor guide withsuggested course placement, prior knowledge, pacing, learning objectives,assessment questions, and guidance for adapting the material to differentinstructional settings. The Tutorial helps students connect textbookthermodynamics to modern functional materials and sustainable coolingtechnologies.