College Chemistry Courses Research Articles

Creation of a stable and highly functional pluripotent stem cell derived hepatocyte model for drug metabolisation and toxicity screening

Introductory college chemistry courses are required by a wide range of science curricula. This fact has tended to frame the courses as places where core, fundamental ideas are taught, so that a foundation of knowledge might be called upon by students when they are in subsequent courses. Unfortunately, the preponderance of compartmentalized fundamental topics bolsters learning that has challenges in terms of transfer of knowledge to other science settings. One method that has been proposed to help alleviate this concern is to incorporate systems thinking and rich contexts that directly connect foundational chemistry ideas to larger systems. One area that shows strong potential for such efforts is the science of pharmaceuticals. Adding examples related to the chemistry of drugs, both within the large lecture setting of general chemistry and within smaller discussion groups. The role of example problems, student writing projects and group construction of systems thinking related visualizations of the context of pharmaceutical chemistry are reported.

Comparison of learning in two context-based university chemistry classes

ABSTRACTContext-based learning (CBL) is advocated as beneficial to learners, but more needs to be understood about how different contexts used in courses influence student outcomes. Gilbert defined several models of context that appear to be used in chemistry. In one model that achieves many criteria of student meaning-making, the context is provided by ‘personal mental activity’, meaning that students engage in a role to solve a problem. The model’s predicted outcomes are that students develop and use the specialised language of chemistry, translate what they learn in the immediate context to other contexts, and empathise with the community of practice that is created. The first two of these outcomes were investigated in two large-enrolment university chemistry courses, both organised as this CBL model, in which students were introduced to kinetic molecular theory (KMT). Sample 1 students (N1 = 105) learned KMT through whole-class kinaesthetic activity as a human model of a gas while focusing on a problem identifying substances in balloons filled with different gases. Sample 2 students (N2 = 110) manipulated molecular dynamics simulations while focusing on the problem of reducing atmospheric CO2. Exam answers and pre-/post-test responses, involving a new KMT context, were analysed. Students in Sample 1 demonstrated a stronger understanding of particle trajectories, while Sample 2 students developed more sophisticated mechanistic reasoning and greater fluidity of translation between contexts through increased use of chemists’ specialised language. The relationships of these outcomes to the contexts were examined in consideration of the different curriculum emphases inherent in the contexts.

Using self-efficacy beliefs to understand how students in a general chemistry course approach the exam process

Retention of students who major in STEM continues to be a major concern for universities. Many students cite poor teaching and disappointing grades as reasons for dropping out of STEM courses. Current college chemistry courses often assess what a student has learned through summative exams. To understand students' experiences of the exam process, including how students prepare for an exam, take an exam, and respond to feedback from an exam, data was collected through interviews with students in an introductory college chemistry course. The interview data was analyzed using emergent coding to describe students' experiences of the exam process using phenomenography. Data indicated that students' experiences with the exam process could be categorized based on their reported exam performance. Overall, differences could be seen between these students' self-efficacy beliefs and metacognitive skills based on the grade each student reported receiving on the exam. The students who performed highest on the exam had self-efficacy beliefs primarily from their mastery experience, and middle performing students' self-efficacy beliefs came from vicarious experience. The lowest performing student had low self-efficacy beliefs. Students who received the highest grades on the exam viewed learning as making meaningful connections between topics, and students who received lower grades viewed learning as memorization. By further understanding students study habits, their views on the exam process, and the development of their self-efficacy beliefs, instructors may be better able to assist low and middle performing students in our general chemistry courses. The findings from this study suggest several ways instructors could facilitate more effective studying and promote higher self-efficacy beliefs, including promoting group work, talking with students about study skills, and encouraging attendance at office hours to review exam responses.

Partial least squares structural equation modeling of chemistry attitude in introductory college chemistry

Students’ decisions to enter or persist in STEM courses is linked with their affective domain. The influence of factors impacting students’ affective domain in introductory college chemistry classes, such as attitude, is often overlooked by instructors, who instead focus on students’ mathematical abilities as sole predictors of academic achievement. The current academic barrier to enrollment in introductory college chemistry classes is typically a passing grade in a mathematics prerequisite class. However, mathematical ability is only a piece of the puzzle in predicting preparedness for college chemistry. Herein, students’ attitude toward the subject of chemistry was measured using the original Attitudes toward the Subject of Chemistry Inventory (ASCI). Partial least squares structural equation modeling (PLS-SEM) was used to chart and monitor the development of students’ attitude toward the subject of chemistry during an introductory college chemistry course. Results from PLS-SEM support a 3-factor (intellectual accessibility,emotional satisfaction, andinterestandutility) structure, which could signal the distinct cognitive, affective, and behavioral components of attitude, according to its theoretical tripartite framework. Evidence of a low-involvement hierarchy of attitude effect is also presented herein. This study provides a pathway for instructors to identify at-risk students, exhibiting low affective characteristics, early in a course so that academic interventions are feasible. The results presented here have implications for the design and implementation of teaching strategies geared toward optimizing student achievement in introductory college chemistry.

Design and Practice of Moral Education in University Chemistry Course

Design and Practice of Moral Education in University Chemistry Course

Tie-Dye! An Engaging Activity To Introduce Polymers and Polymerization to Beginning Chemistry Students

A stand-alone polymer unit, centered on a tie-dye activity, was used to introduce the concept of polymers and the process of polymerization to three different groups of beginning-level chemistry students. This polymer unit consists of three parts. First, each student used a molecular model kit to construct the monomer units, β-d-glucose. Students combined these monomer units to learn the polymerization process and visualize the formation of the cellulose polymer in conjunction with writing the balanced equation for the polymerization reaction. Second, students tie-dyed cotton t-shirts made of cellulose fibers using dyes purchased from local craft stores. Finally, a primary literature exercise engaged students in understanding the chemical reactions that bind the cellulose fibers to the dye molecules permanently, producing a colorfast tie-dyed t-shirt. This stand-alone polymer unit can be used in any beginning college or high school chemistry course to introduce students to polymer chemistry and the process of polymerization. It helped review and reinforce previously learned concepts such as covalent bonding, electronegativity, bond polarity, Lewis structures, bond angles, and molecular geometry using the VSEPR model. As evidenced by the feedback collected from students anonymously after completion of the polymer unit, the three parts in this unit helped them learn the chemistry of polymers and polymerization, and their interest was kindled by the tie-dye activity. The polymer unit was a favorite of students in all three courses.

Development and evaluation of a chemistry-specific version of the academic motivation scale (AMS-Chemistry)

Fundamentally concerned with motivation, self-determination theory (SDT) represents a framework of several mini-theories to explore how social context interacts with people's motivational types categorized by degree of regulation internalization. This paper aims to modify an existing theory-based instrument (Academic Motivation Scale, or AMS) and provide validity evidence for the modified instrument (Academic Motivation Scale-Chemistry) as a measure of seven types of student motivation toward chemistry. The paper explores how motivation as measured by AMS-Chemistry is related to student academic achievement and attendance. In a pilot study, the unmodified AMS showed good reliability, reasonable data fit, and the ability to detect motivational differences by sex in college chemistry courses. Based on the pilot study results, expert panel discussions, and cognitive interviews with students, the Academic Motivation Scale – Chemistry (AMS-Chemistry) was developed. AMS-Chemistry was administered to university students in a first semester general chemistry course twice within a semester. An examination of validity evidence suggested that the AMS-Chemistry data could be used to investigate student motivation toward chemistry. Results showed students were extrinsically motivated toward chemistry on average, and there was an overall motivational difference favoring males with a medium effect size. Correlation studies showed motivation was not associated with academic achievement at the beginning of the term, but intrinsic motivation subscales (to know,to experience, andto accomplish) were positively associated with academic achievement at the end of the term. Results also showed that students who persisted in class attendance scored higher on intrinsic motivation subscales than those who did not persist. The 28-item AMS-Chemistry is easy to administer and can be used to better understand students’ motivation status and how it might change across the curriculum. Faculty interested in promoting student intrinsic motivation may also use the AMS-Chemistry to evaluate the impact of their efforts.

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.

Exploration and Practice for the Management of University Chemistry Course

On the basis of the specific conditions of Beijing Institute of Graphic Communication, the methods applied in the management of university chemistry courses were detailedly described in this paper. Experiments are particularly important parts in the university chemistry class because they can not only impart knowledge and skills, but also improve the comprehensive quality and abilities of students. Experiments in the university chemistry class have multiple forms, mainly including two aspects: verification experiments and exploration experiments. The verification experiments include student experiments and demonstration experiments. In order to cultivate students' scientific literacy, exploration experiments are using the physical and chemical practice innovation base as the platform, taking the students' scientific research of Beijing Institute of Graphic Communication as the starting point and then using the scientific research of the university students in Beijing as the driving force. In addition, the regular organization of the university students' chemistry competition is also an important aspect of the management and construction of chemistry course.

The Innovative Teaching Practice on College Chemistry Course for the Innovative Experimental Class

The Innovative Teaching Practice on College Chemistry Course for the Innovative Experimental Class

When do students recognize relationships between molecular structure and properties? A longitudinal comparison of the impact of traditional and transformed curricula

The ability to use a chemical structure to predict and explain phenomenon is essential to a robust understanding of chemistry; however, previous research has shown that students find it difficult to make the connection between structure and properties. In this study we examine how student recognition of the connections between structure and properties evolves during the first two years of college chemistry courses. In addition, we investigate how an alternative general chemistry curriculum (Chemistry, Life, the Universe and Everything (CLUE)) impacts students' understanding during these first two-years. Using discrete-time survival analysis to analyze student responses to the Implicit Information from Lewis Structures Instrument (IILSI), we found that it takes multiple semesters for students enrolled in a traditional curriculum to recognize that chemical structures can be used as models to predict chemical and physical properties. Students in the CLUE curriculum, however, tend to make this connection earlier than a matched cohort of students from a traditional curriculum, and this advantage is maintained throughout the two semesters of organic chemistry. In general, the control group takes an additional year of organic chemistry to reach the same level as the CLUE students after a year of general chemistry.

Quantifying Gold Nanoparticle Concentration in a Dietary Supplement Using Smartphone Colorimetry and Google Applications

Spectrophotometry and colorimetry experiments are common in high school and college chemistry courses, and nanotechnology is increasingly common in every day products and new devices. Previous work has demonstrated that handheld camera devices can be used to quantify the concentration of a colored analyte in solution in place of traditional spectrophotometric or colorimetric equipment. This paper extends this approach to quantifying the concentration of gold nanoparticles in a colloidal gold “dietary supplement”. With the addition of free Google applications, the investigation provides a feasible, sophisticated lab experience and introduction to nanotechnology.

Sex difference in spatial ability for college students and exploration of measurement invariance

This study investigates psychometric evidence for a spatial ability instrument with a focus on measurement invariance and sex difference in this domain. The Purdue Visualization of Rotations (ROT) test was administered to science major students enrolled in a college chemistry course to measure mental rotation ability. Confirmatory factor analysis (CFA) was used to evaluate the fit of three alternative models. A bi-factor model is a better fit for the data than other models (1-factor, 4-factor 2nd-order), which indicates that the probability of answering a test item correctly is affected not only by student ability but also by an item-writing pattern. Results from multiple-group CFA support the measurement invariance of the bi-factor model between sexes and the outperformance of males over females with medium to large effect sizes. In conclusion, the ROT is appropriate to measure student mental rotation ability in college classrooms and to detect a difference between sexes.

Exploring the Use of Faded Worked Examples as a Problem Solving Approach for Underprepared Students

<p>It is not uncommon for students to find themselves underprepared when entering a post secondary institution. In additional to lower levels of academic achievement, underprepared students may not be aware that they lack the skills needed to be successful and effectively acquire and process information. Because of this, students that enter post-secondary institutions underprepared often require more support in and out of the college classroom.</p><p>In computational based classes, such as math, engineering, chemistry or physics, this support often includes an introduction to effective problem solving strategies. This study introduced faded worked examples as a problem solving approach to students identified as mathematically underprepared in a college chemistry course. Faded worked examples are similar to worked examples but fade out steps for students to complete, allowing support within the problem solving approach as learning improves. The goal of this study was to explore students’ perceptions of this problem solving approach and their belief in its potential to enhance their learning, particularly with students identified as academically underprepared. Overall, students reported that faded worked examples enhanced their overall learning and problem solving abilities in chemistry and the step by step process allowed for a better understanding of the course material.</p>

A Fresh Look at the Crystal Violet Lab with Handheld Camera Colorimetry

Chemical kinetic experiments to determine rate laws are common in high school and college chemistry courses. For reactions involving a color change, rate laws can be determined experimentally using spectrophotometric or colorimetric equipment though this equipment can be cost prohibitive. Previous work demonstrated that inexpensive handheld camera devices can be used to quantify the concentration of a colored analyte in solution. This paper extends this approach to the kinetic study of the color fading of crystal violet upon reaction with sodium hydroxide. The results demonstrate accurate determination of the reaction order, with respect to crystal violet, using a method accessible in many high school and college laboratories.

The Use of POGIL Teaching Strategy Increases Student Learning of Basic Pharmacology Concepts

Process‐oriented guided inquiry learning (POGIL) is an active learning, team‐based teaching strategy that has been used in college chemistry courses to promote deeper understanding and develop higher‐order thinking skills. The use and evaluation of the POGIL strategy in pharmacology courses has not been reported. Our hypothesis is the use of the POGIL strategy will increase student overall exam performance, specifically exam questions requiring higher level thinking skills.Data were collected over a three‐year period from a first professional year pharmacy course. In 2011, content was presented using a lecture‐based format and then, in 2012 and 2013 the same content was covered using the POGIL strategy. Comparisons included overall performance on exams and on question sets classified as requiring either lower order thinking skills (knowledge, comprehension) or higher order thinking skills (application, analysis). Statistical comparisons made using one way analysis of variance. Data are reported as means + standard errors.Overall exam scores improved significantly when moving from a lecture‐based course (80.0%+0.8) in 2011 (N=112) to using the POGIL strategy (84.0%+0.8 and 83.2%+0.8) in 2012 (N=111) and 2013 (N=111), respectively (p<0.01). On those questions classified as requiring higher order thinking skills, student performance significantly increased from 75.8%+1.0 in 2011 to 83.1%+1.1 and 82.5 %+1.2 in 2012 and 2013 when the POGIL strategy was used (p<0.01). Performance on lower order thinking skills was unchanged (92.0%+0.9, 91.6%+1.0, and 91.3%+1.1 p=0.70).The use of the POGIL teaching strategy increased student performance on questions requiring higher order thinking skills, suggesting the strategy is effective in promoting deeper learning and problem solving skills.

Styrofoam-and-Velcro: An Alternative to Ball-and-Stick Models.

For students learning biology at introductory levels, one of the most significant instructional barriers is their lack of preparation in chemistry. In upper-division college chemistry and biology courses, students employ ball-and-stick models in order to visualize molecular structures, but at the introductory biology level, models are inconsistently used and at the secondary level they are avoided altogether. Traditional ball-and-stick models perform poorly at all levels because they only show bonds, never valence electrons. This poses a problem for students who are visual or kinesthetic learners, as modeling electrons in the bonding process may be critical to understanding the mechanisms behind the biochemical reactions that serve as a foundation for biological concepts. Our molecular modeling kits show the action of valence electrons and correctly deal with the issue of polarity and partial charge, while still illustrating structure and function similarly to ball-and-stick models, allowing students to model nearly every reaction or molecule they may need to learn. Additionally, this kit will foster model building exercises required as part of the Next Generation Science Standards ( http://www.nextgenscience.org/next-generation-science-standards ). This model was devloped in conjunction with 'Molecular Twister: A Game for Exploring Solution Chemistry' (JMBE Vol 15, No 1; http://jmbe.asm.org/index.php/jmbe/article/view/652 ) by the same authors, which uses principles derived from the present paper.

Infusing Sustainability Science Literacy through Chemistry Education: Climate Science as a Rich Context for Learning Chemistry

Global science is paying increasingly urgent attention to sustainability challenges, as evidenced by initiatives such as the working group determining whether Earth has moved from the Holocene to the Anthropocene Epoch on the geologic time scale and the interdisciplinary efforts to define and quantify our planetary boundaries. Despite the fact that much of the scientific work underlying these initiatives is based on measurements of fundamental chemistry parameters, sustainability literacy has not been incorporated in any systematic way into the undergraduate chemistry curriculum. We report here on the philosophy and implementation of a NSF-funded initiative, Visualizing the Chemistry of Climate Change (VC3), which provides an exemplar for developing strategies to fill that gap, focusing on climate change, one of the defining sustainability challenges of the 21st century. VC3 targets the strategic first year university and college chemistry courses that are common to the program requirements of many scienc...

Investigation of Absolute and Relative Scaling Conceptions of Students in Introductory College Chemistry Courses

Scale as a theme in science instruction is not a new idea. As early as the mid-1980s, scale was identified as an important component of a student’s overall science literacy. However, the study of scale and the scale literacy of students in varying levels of education have received less attention than other science-literacy components. Foremost into the foray of students’ scale literacy has been the research by Gail Jones and co-workers, who have been studying students in middle and high school, in-service teachers, and experts in their respective fields. However, the scale literacy of students in undergraduate college chemistry courses is unknown. One should not assume that students in introductory chemistry courses have an appropriate and developed conception of scale, particularly down to the relevant size realms for chemistry. The research presented here investigates the relative and absolute scaling conceptions of students in introductory chemistry courses.

Filling a Plastic Bag with Carbon Dioxide: A Student-Designed Guided-Inquiry Lab for Advanced Placement and College Chemistry Courses

A guided-inquiry lab, suitable for first-year general chemistry or high school advanced placement chemistry, is presented that uses only inexpensive, store-bought materials. The reaction of sodium bicarbonate (baking soda) with aqueous acetic acid (vinegar), under the constraint of the challenge to completely fill a sealable plastic bag with the gaseous carbon dioxide product, is presented to students of chemistry. Students must marshal their knowledge of non-STP gas stoichiometry, including the often misunderstood concept of limiting and excess reagents, to successfully complete the task. This contribution is part of a special issue on teaching introductory chemistry in the context of the advanced placement (AP) chemistry course redesign.