教学课程资源库 更多>>

关键词： Student success   Higher education   At-risk students   Underrepresented students   Organic chemistry  

摘要： In the USA, Organic Chemistry I is a gateway course for undergraduate students seeking careers in medical- and health-related fields. Estimates of failure and withdrawal rates are approximately 40% at some large, public institutions and higher for specific segments of the student population, such as ethnic minorities, those of low socio-economic status, and non-traditional students. We applied a multi-layered contextual model of student success to investigate various factors contributing to the academic success of undergraduate students in Organic Chemistry I. Participants were 20 undergraduate students formerly enrolled in Organic Chemistry I at an urban, 4-year public institution located in the northeastern USA. Using semi-structured interviews, we examined students' divergent academic outcomes, as well as internal, proximal, and distal variables relating to positive academic outcomes. Results suggest that at-risk students' success in Organic Chemistry I is facilitated by support from qualified mentors, availability and utilization of academic resources, and proficiency in science. We discuss these results within a contextual framework and offer practical suggestions for educators.

摘要： A review presenting water as the logical reaction medium for the future of organic chemistry. A discussion is offered that covers both the "on water" and "in water" phenomena, and how water is playing unique roles in each, specifically with regard to its use in organic synthesis.

关键词： Second-Year Undergraduate   Organic Chemistry   Hands-On Learning/Manipulatives   Acids/Bases   NMR Spectroscopy   Organosulfur Compounds   Precipitation/Solubility  

摘要： The practical two-step synthesis of 1-phenylthiourea is reported here as an undergraduate experiment for the organic synthesis laboratory. The reactions involved in 1-phenylthiourea preparation are very useful didactic examples to illustrate concepts relating to carbonyl substitution and addition, the effect of pH on solubility of organic compounds, and many laboratory techniques, such as isolation, purification, and product analysis. The products were purified through precipitation, which involves changing the pH value, followed by recrystallization. The products were identified by melting point and infrared and NMR spectroscopy.

关键词： Second-Year Undergraduate   Organic Chemistry   Laboratory Instruction   Hands-On Learning/Manipulatives   Acids/Bases   Dyes/Pigments   Physical Properties   Separation Science  

摘要： Herein, we describe an accessible and safe organic chemistry lab experiment that can be completed at home. Liquid-liquid extraction is a fundamental organic chemistry lab experiment that touches on topics such as chemical structure, density, solubility, and acid-base chemistry. Given the increased demand for safe organic chemistry experiments that can be performed in the at-home environment, we have adapted the conventional wet lab liquid-liquid extraction experience by using food colorants. Students are first guided through sample questions to establish a basic understanding of solubility, acid-base chemistry, and separation via extraction techniques. Next, they are given unknown dye mixtures which they subject to liquid-liquid extraction using a plastic soda bottle with vegetable oil, water, white vinegar, and sodium bicarbonate. All materials are readily available and food-safe, making the experiment amenable to the at-home environment while still allowing students to physically engage in a foundational lab experiment.

关键词： Laboratory Instruction   Second-Year Undergraduate   Organic Chemistry   Computer-Based Learning   Inquiry-Based/Discovery Learning   Alkenes   Elimination Reactions  

摘要： The dehydration of 2- or 4-methylcyclohexanol to obtain isomers of methylcyclohexene is a classic organic chemistry experiment. Students perform a distillation, collecting samples to analyze the progress of the reaction. The reaction produces a major product that can be explained on the basis of the regiochemistry of the pi bond formation for the alpha-beta elimination process. Minor products can be attributed to the possible rearrangement of the carbocation through a hydride shift. We have added computational analysis to this classic experiment to help students understand alkene stability. The experiment was performed early in the sophomore organic chemistry laboratory, before students were introduced to the mechanistic perspectives that govern the reaction. The iSpartan analysis of the possible methylcyclohexene products combined with gas chromatography data provides students with an inquiry-based laboratory experience. A novice student can analyze the computational information about the products to determine the trend in product stability and determine if a double-bond is formed at an unexpected location in the molecule. The integration of computational tools provides more information to students than performing the experiment in isolation.

关键词： Organic Chemistry   Second-Year Undergraduate   Computer-Based Learning   Multimedia-Based Learning   Testing/Assessment  

摘要： Interactive learning is one of the approaches that is very important to explore in higher education. Chemistry students own smartphones, laptops, and tablets and could use appropriate apps to complement traditional forms of learning. Here we introduce a new app, MILAGE LEARN+, which integrates several teaching strategies, such as mobile learning, autonomous learning, peer review, blended learning, and gamification. These strategies were evaluated by the student users through an electronic survey form containing 15 statements with responses graded on a Likert-type scale. Students rate the usage of novel teaching/learning strategies in the MILAGE LEARN+ app as something very positive. There is a positive correlation between the relative grades obtained using MILAGE LEARN+ and the final exam grades. Thus, in this experience, students with better results in MILAGE LEARN+ also had better results in the final exam.

关键词： Mixtures   Evaporation   Solvents   Organic synthesis   Nuclear magnetic resonance spectroscopy  

摘要： A nuclear magnetic resonance (NMR) spectrometer is a key instrument in the organic synthesis laboratory for structure determination, reaction control, and compound purity analysis. In addition to qualitative analysis, the application of NMR for quantitative analysis (qNMR) is gaining popularity. qNMR allows for simple quantification of crude product mixtures, determination of reaction yields, and purity of organic compounds. The determination of NMR yield requires the addition of an internal standard to each sample. Herein, we report a method where CDCl3 residual solvent signal is used as an internal standard for qNMR after quantification in the solvent batch. This method significantly simplifies sample preparation and allows straightforward recovery of the analyte by the simple evaporation of the NMR solvent. The accuracy of the method is comparable to qNMR with 1,3,5-trimethoxybenzene as an internal standard if the herein described guidelines are followed.

关键词： 课程思政   学习目标   教学内容   糖类化合物  

摘要： 为充分挖掘有机化学课程糖类化合物章节中的思政元素,发挥专业课程在立德树人方面的重要作用,我们对该章节的学习目标进行了梳理,并据此设计了学习内容,构建了以糖类化合物知识为主体,以糖的结构和合成研究史、有机化学学科思想、中国在糖化学研究中的贡献等人文素材为主导的糖类化合物章节教学体系。