Search

This research focuses on students' higher-order cognitive skill (HOCS)-oriented learning to construct effective hierarchical thinking abilities in their chemical particulate nature of matter. For in-depth knowledge and profound understanding, this research deals with students' positive developments towards HOCS with a special guidance to Marzanos' taxonomy. The methodology starts from the retrieval and comprehension of HOCS-centered assessment instrument to students' analysis and knowledge utilization of transitional performances. 326 participants were assigned to take natural science curriculum in 2019 academic year. With the help of 7 scholars' implements, the importance of content validity and inter-rate reliability were constructed through instrument developments of students' HOCS performances. All research results indicated that more distributions of HOCS thinking abilities reached up to the target response of 38.0% analysis task and 27.30% knowledge utilization in Marzanos' spectrum. This research is beneficial and advantageous that students will be capable of additional learning efficiency in their multiple interactive engagements with academic resources and suggestions from instructors, researchers, and science educators.

To be familiar with micro and symbolic performances, students could work out more effective approaches of innovated techniques known as five hierarchical designs in chemistry equilibrium. However, the most frequently reported problem in students' assessment of chemistry study is attributed to their poor skill recognizing basic concepts. The aim of this research was to construct the 6 test items to help undergraduate students assess their high-order and low-order cognitive skills as a deeper framework of particle representations. It takes a dynamic appeal for students to identify their profound understanding of cognitive skills in accordance with their potential performances of particle representations. In this research, students activate the test instrument to sustain their development of content validity and inter-rater reliability. The research results mark a different responsive engagement of both high-order and low-order cognitive skills in students' total performances with the skill ratio score of 1:6 for conceptual recognition and analyses of micro and symbolic performances. All students' micro and symbolic performances offer an indication for understanding their advanced cognitive skills in the particulate nature of matter. It is beneficial to improve new perspectives in the discussions and activity hierarchical designs in their chemistry equilibrium classrooms.

The global COVID-19 pandemic has had a significant impact on university course design, implementation, and instruction, with many courses being offered remotely rather than face-to-face to prevent the spread of COVID-19. As the COVID-19 pandemic subsides, more and more courses are transitioning back to face-to-face instruction. In this article, we describe the design and implementation of an advanced synthetic chemistry laboratory course that was taught face-to-face during the COVID-19 pandemic and prior to the mass distribution of COVID-19 vaccines. We were able to utilize physical distancing as a teaching strategy, along with personalized scheduling of experiments, designated pathways, individual workstations and lab kits, enhanced sanitation, and self-reflection exercises, to create a course with a significant focus on the individual student experience. Instructor reflections suggest that this course was well-received by both instructors and students and was successful in meeting the course learning objectives while maintaining the health and safety of all participants.

Many electroanalytical techniques utilize three-electrode systems consisting of reference, counter, and working electrodes. These electrodes are often expensive when purchased commercially, making low-cost alternatives a vital area of research. Cheaper alternatives have been proposed; however, they often require time-consuming assembly techniques or materials that are difficult to work with. This technology report outlines the production and testing of an Ag/AgCl reference electrode, a platinum (Pt) counter electrode, and a carbon paste working electrode. These electrodes have been designed using 3D printing technology, which has become increasingly more available at educational institutions. By utilizing 3D printing technology, these adaptable designs can be produced quickly and at a fraction of the cost of commercially available electrodes. The lab-made Ag/AgCl reference and Pt counter electrodes were tested via cyclic voltammetry (CV) experiments with orange juice and ruthenium hexaamine as analytes. The results obtained were statistically similar in all obtained measurements. The carbon paste working electrode was tested in potassium ferricyanide for both variable scan rate and concentration responses. In these tests, the lab-made electrode performance compared favorably to commercial electrodes. This demonstrates the viability of our method in the production of low-cost, reliable electrodes that can be used in a variety of electroanalytical experiments.

This report showcases a new type of online homework system that provides students with a free-form interface and dynamic feedback. The ORCCA Tutor (Open-Response Chemistry Cognitive Assistance Tutor) is a production rules-based online tutoring system utilizing the Cognitive Tutoring Authoring Tools (CTAT) developed by Carnegie Mellon University. In this report, we discuss the interface design and the production rules that allow for a multitude of chemistry calculations to be solved in a wide variety of ways by students. We discuss improvements of the software, already implemented or planned for the future, based on think aloud/interviews with students.

The use of animated concept mapping (ACM) has been linked to an innovative learning skill when conducting students' guidance of 4 corresponding reasoning processes in electrochemistry. This research aims to establish a new perspective with ACM cognitive reasoning to broaden students' individual developments of problem-solving skills. It is followed by a quasi-experimental approach of pre-tests, post-tests and retention-tests designed for 274 qualified college students in Taiwan. All data collected from students' learning performances and feedback is further analyzed by means of achievement covariance, t-tests and one-way ANOVA. Analytical results reveal that ACM facilitates learning comparisons and out-performances in two groups of students in different post-test and retention-test scores. Students' positive feedback and learning disposition also provide the predominant advantage for participants' successful reasoning processes. Pedagogical implications suggest that ACM learning performances result in more significant collaborative reasoning.

This research focuses on students' tactic assessments of 3 correlations with illustrated 2-step strategic map and animated presentations in stoichiometry. The participants were divided into 2 learning groups: the experimental and the control group by quasi-experimental approach. Most of all, experimental group participants have been contingent on critical performances of thinking capabilities in accordance with tactic fulfillments of 3 correlations helpfully. In contrast with statistic findings of post-tests, experimental group participants get more formulated goals of individual learning in answering 5 algorithmic and conceptual pairs of achievement test items than those of control group participants. Students' shift of reasoning from model-based to case-based requires them to explore an effective mental cognition and responses for full-fledged performances of problem-solving skills. After tactic fulfillments for 3 study objectives of visualized developments, experimental group participants have upgraded a distinct learning accumulation and project-based feedback at their best learning performances.

This study better research aimed King-Dow Su at strategic applications for exploring students' learning performances with conceptual understanding and algorithmic proficiency by problem-solving maps and six major learning activities. A quasi-experimental method was employed to detect the outcomes of students' compared intervention, together with two learning groups, the experimental group and control group. All results demonstrated that the experimental group students who used the strategic applications showed better learning performances than those of the control group students. The experimental group students with more cognitive competency presented significant achievements and larger effect sizes after their two module executions of gas chemistry program. Moreover, these demonstrations were predominated with students' conceptual and algorithmic learning developments in chemistry. The experimental group students witnessed a new advancement of self-performed modules to promote their feedback and intelligent analyses.

An innovative food laboratory for a chemistry of food and cooking course has been developed for nonscience majors and under-represented students in science. To help these students succeed in science, a laboratory was designed to engage students using food and cooking as a medium for building a stronger foundation in chemistry. Each food laboratory included a chemistry experiment paired with a food preparation that reinforced the chemical principles addressed. The chemistry experiments covered topics that are found in conventional first-year general chemistry courses but instead used food ingredients and kitchen equipment. The food preparations were designed based on chemical concepts that the students learned from the initial chemistry experiments. The food laboratories were found to engage students when chemistry experiments were paired with food preparations. Through this pilot food laboratory we have gained valuable insights into teaching fundamental chemistry to nonscience students.

Students with and without learning disabilities in high school chemistry classes, either co-taught or self-contained, received instruction on calculating molar conversions using universal design for learning (UDL) or business-as-usual techniques. For Study 1, posttest scores of students with and without learning disabilities (LD) in co-taught classes who received the UDL treatment are compared with peers' scores in the comparison group. For Study 2, posttest scores from students with LD who received UDL treatment in a self-contained special education class are reported. Students in the UDL treatment scored significantly higher on posttests than comparison group peers in Study 1. Mean scores for students with LD in Study 2 were similar to UDL students in Study 1. Social validity feedback on the UDL instruction was positive. Implications for UDL chemistry instruction and future research are described.

With the amount of data available through an online homework system about students' study habits, it stands to reason that such systems can be used to identify likely student outcomes. A study was conducted to see how student usage of an online chemistry homework system (OWL) correlated with student success in a general chemistry course. Online chemistry homework activity was examined for first-year students taking general chemistry at a midsize, private university. The six different chemistry question sets examined were: bond properties; standard molar enthalpy; electronegativity; Lewis dot structures; calorimetry; and stoichiometry. Students' OWL activity was then correlated with their exam grades and their final course grades. Results showed that higher average time spent per question correlated positively with student success as measured by final grades. However, multiple attempts per question correlated negatively with student success. A multiple linear regression model and other guidelines are presented for instructors' use to identify chemistry topics where students may need additional instruction to improve their understanding.

Low cost, open-source analytical instrumentation has the potential to increase educational outcomes for students and enable large-scale citizen science projects. Many of these instruments rely on smartphones to collect the data, mainly because they can effectively leverage a dramatic price-to-performance ratio of the optical sensors. However, several hurdles need to be overcome for these devices to be more widely adapted. In this communication we focus on visible spectrophotometers, which are common in chemistry laboratories because of the day-to-day need for quantifying concentration. To make smartphone-based spectrometers practical for wider use, we have designed a 3D-printable spectrophotometer with a dual-beam optical geometry. This geometry allows for sample and reference data to be collected on the same photograph and thus improves the signal-to-noise ratio and reproducibility of the spectra. A universal mounting system was also developed to allow for a wide variety of smartphone form factors to be coupled to the spectrophotometer. To demonstrate potential applications of this device, two assays are reported. The first is a simple illustration of the Beer--Lambert Law with common household dyes. The second is a colorimetric nitrate assay, which shows a quantitative relationship between absorption and nitrate concentration. Kinetic data are also shown for the nitrate assay, which illustrate the long time-stability of the spectral data acquired from the device.

Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and computational chemistry are used in concert to evaluate the thermal decomposition of calcium acetate monohydrate, Ca(C[subscript 2]H[subscript 3]O[subscript 2])[subscript 2]·H[subscript 2]O, and to engage students in high-level thinking as they synthesize results from several techniques. Students use TGA to generate and isolate the reaction intermediates and final product. Three common TGA transitions (the loss of water, the generation of a metal carbonate, and the generation of a metal oxide) with very different reaction temperatures are observed with this sample. The resulting four samples (starting material, two intermediates, and final product) are then analyzed by FTIR. Students are able to observe the progress of the reaction through a comparison of the IR spectra, via the change of water, O-H, and C-H signals. The computational analysis of the vibrational frequencies of carbonate is performed to demonstrate the concepts of predicting the number of principal vibrational frequencies, vibrational degeneracy, and IR activity in addition to aiding in the identification of the second decomposition intermediate, CaCO[subscript 3]. This integrated approach also encourages students to appreciate the strengths and weaknesses of various techniques and recognize that often chemical analysis requires the use of multiple tools.

The purpose of this study is to design information communication technology (ICT) courses related to experimental chemistry for junior college freshmen (aged from 16 to 18), entitled "ICT-integrated environmental learning", and to assess the learning performance of these students after completing the courses. This study adopts a quasi-experimental approach to evaluate the learning of two groups of students after completing a nine-week semester syllabus. Aided by ANCOVA data, we probe the processes of the students' chemistry learning, its effectiveness and their attitudes. The result analyses verify that our ICT-integrated environmental learning has a more significant effect on the students' learning performance. Therefore, it is our goal to design an effective approach for upgrading students' cognizance and learning attitudes. The results obtained from our ICT-integrated environmental learning when compared with other chemical experimental results show the same positive and scientific perspective for academic research. (Contains 8 tables and 1 figure.)

A reference electrode is an essential component of all three-electrode electrochemical measurements. Common commercial reference electrodes, including the saturated calomel electrode and Ag/AgCl reference electrode, are expensive with the former containing toxic mercury. Cheaper alternatives have been proposed including Ag/AgCl references made from pipets and test tubes. However, electrodes prepared in this way are difficult to work with and are limited by the size and shape of glass casings that are available. This paper proposes an in-house manufactured Ag/AgCl reference electrode that uses some 3D-printed components in the fabrication process. This electrode is cheap to manufacture ($5 vs $60-100 CAD for the commercial reference electrode), and the design can be quickly altered due to the 3D printer's capabilities in rapidly printing new electrode shapes to suit different analysts' needs. The lab-made reference electrodes demonstrated stability and consistency in peak potential measurements in the cyclic voltammetry (CV) experiments. In ferricyanide CV tests, the recorded differences in anodic and cathodic peak potential ([delta]E[subscript p) values for the commercial reference electrode and both lab-made electrodes were 68 ± 9%, 70 ± 12%, and 69 ± 13%, respectively. For all tests, the results were statistically comparable with those of the commercial Ag/AgCl reference electrode.

Developing simpler, more accessible, and more affordable methods for the determination of the boiling point of microscale amounts of liquid may lead to increased utilization in research and teaching laboratories as an analytical technique. Our efforts toward that goal have revealed that digital hot plates can be used as the heat source. One option is to simply use a test tube and a digital thermometer, requiring 300 µL of liquid that accurately determines boiling points that range from 35 to 150 °C. An alternative method, requiring as little as 30 µL of liquid, utilizes a modified aluminum block and a temperature control probe coupled to the digital hot plate that results in the accurate determination of boiling points that range from 35 to 205 °C. Both modifications to the Siwoloboff-Wiegand method provide consistent, reliable, and accurate boiling points for a variety of liquids with a wide range of boiling points.

We implemented a laboratory curriculum reform to teach foundational concepts in chemistry, particularly those concepts related to healthcare, in a chemistry course for prenursing students. Here, we discuss the reform, exploring how students built upon understandings gained in lab and correlating lab learning to course outcomes. We further discuss shifts in student work as they move through the course. As the course progressed, students became familiar with the pedagogy but also faced more challenging tasks. We present details on several of the laboratories that build the groundwork for understanding chemical principles, including the following: intermolecular forces, physical properties, acid-base chemistry, equilibrium, and chemical reactions. We further share our observations of student interactions around in-lab prompts and activities, and how these interactions inform our teaching. Our reform aims to improve critical thinking skills, namely, making and using models, observation skills, reasoning with evidence, and applying concepts to new problems. The laboratory procedures presented here modify those commonly found in the chemistry curriculum with a consistent student-centered pedagogy. We hope the simplicity and popularity of the lab procedures will allow for broad implementation of Rickey's MORE (Model, Observe, Reflect, Explain) pedagogy, and we hope our lessons in implementation will broadly benefit those who are implementing new lab curricula.

Despite the importance of asymmetric catalysis in both the pharmaceutical and commodity chemicals industries, asymmetric catalysis is under-represented in undergraduate chemistry laboratory curricula. A novel guided-inquiry experiment based on the asymmetric aldol addition was developed. Students conduct lab work to compare the effectiveness of different catalysts in catalyzing the asymmetric aldol addition of a ketone and an aldehyde. Working in pairs, students use a variety of analytical techniques including 1-D and 2-D NMR spectroscopy and chiral chromatography and write their final report in the format of an ACS style publication. Although this experiment was designed for an advanced undergraduate synthesis laboratory course, it can be readily adapted for use in an organic or an inorganic laboratory course.

Fluorescence spectra excited by laser pointers have been the subject of several papers in "TPT". These papers all describe a fluorescence phenomenon in which the reflected laser light undergoes a change in color: this color change results from the combination of some partially reflected laser light and additional colors generated by fluorescent emission. Here we examine the fluorescence spectra of highlighter inks using green and violet laser pointers. We use an RSpec Explorer spectrometer to obtain spectra and compare the emission spectra of blue, green, yellow, orange, pink, and purple highlighters. The website Compound Interest details the chemical composition of highlighter inks; in addition, the site discusses how some base dye colors can be combined to produce the variety commercially available colors. Spectra obtained in this study were qualitatively consistent with the Compound Interest site. We discuss similarities and differences between various highlighter colors and conclude with the relevance of such studies to physics students.

Introductory Chemistry laboratories must go beyond "cookbook" methods to illustrate how chemistry concepts apply to complex, real-world problems. In our case, we are preparing students to use their chemistry knowledge in the healthcare profession. The experiment described here explicitly models three important chemical concepts: dialysis of small molecules (dye), reversible binding (dye binding to albumin), and competitive binding (dye and a competitor binding to albumin). Moreover, each concept is intimately related to a physiological phenomenon: dialysis is used to treat renal failure, drugs travel in the blood bound to albumin, and competitive albumin binding is a common drug-drug interaction. In the context of this simple series of experiments, students create models, use evidence to validate their models, and finally use their understanding to describe physiological phenomena. This laboratory experiment was implemented in a 100-level course for predominantly prenursing majors. Student pre- and postlab models were examined, illustrating an improved conceptual understanding upon performing the lab and use of evidence to improve or support models. This experiment can be performed in 1 h, and can be adapted as a lecture demonstration.

Learning science in the middle years can be an emotional experience. In this study, we explored ninth-grade students' discrete emotions expressed during science activities in a 9-week unit on chemistry. Individual student's emotions were analyzed through multiple data sources including classroom videos, interviews, and emotions diaries completed at the end of each lesson. Results from three representative students are presented as cases within a case study. Using a theoretical perspective drawn from theories of emotions founded in sociology, three assertions emerged. First, students experienced frustration when learning new chemistry concepts. Second, frustration was resolved through student-student and teacher-student interactions. Third, frustration was transformed when students were afforded time to revisit new concepts. Furthermore, the teacher's identification of students' emotions enabled differentiation of learning through individualized interactions. Finally, we explain how the temporality of emotions emerged as an important phenomenon and suggest an elaboration to Turner's theorization of emotions.

High school students with and without learning disabilities in two chemistry classes accessed technologically-enhanced worksheets, called Pencasts, when completing homework assignments. In this action research study, feedback from students was gathered via questionnaires and interviews. Students most frequently used Pencasts to figure out how to solve homework problems, and all students expressed satisfaction with using Pencasts. Students shared other ways they used Pencasts, such as studying for chemistry tests, and shared how they could benefit if Pencasts were available in other classes. According to the teacher, students with and without disabilities completed the majority of homework when Pencasts were available, and almost all students earned "A" grades on homework. Teacher reflections about Pencasts, implications for practice, and future research are described.

There is on-going international interest in the relationships between assessment instruments, students' understanding of science concepts and context-based curriculum approaches. This study extends earlier research showing that students can develop connections between contexts and concepts--called "fluid transitions"--when studying context-based courses. We provide an in-depth investigation of one student's experiences with multiple contextual assessment instruments that were associated with a context-based course. We analyzed the student's responses to context-based assessment instruments to determine the extent to which contextual tests, reports of field investigations, and extended experimental investigations afforded her opportunities to make connections between contexts and concepts. A system of categorizing student responses was developed that can inform other educators when analyzing student responses to contextual assessment. We also refine the theoretical construct of "fluid transitions" that informed the study initially. Implications for curriculum and assessment design are provided in light of the findings.

As in many countries, public school students in the Philippines have lower levels of achievement compared to private school students. We study whether there is a motivation gap related to this achievement gap by assessing a range of motivational constructs (sense of self, facilitating conditions, and achievement goals) drawn from personal investment theory of motivation, and examining how these constructs predict various school outcomes. Filipino students (N = 1,694) enrolled in high school Chemistry from private and public high schools participated in the study. Multivariate Analysis of Variance indicated that public school students reported less support for schooling from their social groups, lower academic related self-concept, and lower achievement goals compared to private school students. Multiple regression analyses indicated that motivational variables explained a significant amount of variance in achievement and school engagement.

In this exploratory study, students in four co-taught high school chemistry classes were randomly assigned to a Universal Design for Learning (UDL) treatment or a comparison condition. Each co-teaching team taught one comparison and treatment class. UDL principles were operationalized for treatment: (a) a self-management strategy (using a mnemonic, IDEAS) for the multi-step mole conversion process; (b) multi-media lessons with narration, visuals, and animations; (c) procedural facilitators with IDEAS for conversion support; and (d) student workbooks mirroring video content and containing scaffolded practice problems. All students completed a pre-test, post-test, and a 4-week delayed post-test. There were no significant differences between conditions; however, there was an interaction effect between students with and without disabilities for post-tests. Social validity indicated students found IDEAS helpful. Implications for future research include continued focus on disaggregated learning outcomes for students with and without disabilities for UDL interventions, and refinements for UDL interventions that benefit students with and without disabilities.

Curriculum developers and researchers have promoted context-based programmes to arrest waning student interest and participation in the enabling sciences at high school and university. Context-based programmes aim for student connections between scientific discourse and real-world contexts to elevate curricular relevance without diminishing conceptual understanding. This interpretive study explored the learning transactions in one 11th grade context-based chemistry classroom where the context was the local creek. The dialectic of agency/structure was used as a lens to examine how the practices in classroom interactions afforded students the agency for learning. The results suggest that first, fluid transitions were evident in the student-student interactions involving successful students; and second, fluid transitions linking concepts to context were evident in the students' successful reports. The study reveals that the structures of writing and collaborating in groups enabled students' agential and fluent movement between the field of the real-world creek and the field of the formal chemistry classroom. Furthermore, characteristics of academically successful students in context-based chemistry are highlighted. Research, teaching, and future directions for context-based science teaching are discussed. (Contains 1 table,)

Because of the rapidly changing nature of chemical instrumentation, students must be trained in how to learn and understand new instruments. Toward this end, students are asked to create small instrument manuals, or instrument profiles, for the major pieces of equipment studied during an instrumental analysis course. This writing-intensive process of creating instrument profiles requires that students understand the basics of each type of instrument and that they are able to compare the instrument to other instruments. With the use of block and schematic diagrams, the major components within an instrument are emphasized such that students can discover subtle differences between types of instruments. Students' ability to teach themselves new instruments is demonstrated at the end of the semester by creating an instrument profile for an instrument not specifically discussed during the course and by giving a short oral presentation to the class, providing everyone with brief exposure to many more technologies. (Contains 2 figures.)

Following the publication of the higher education white paper increasing entry tariff and widening participation have become even more important issues for universities. This report examines the relationship between entry tariff and undergraduate achievement in Biosciences at the University of Exeter. We show that, whilst there is a significant correlation between A-level tariff and both level 1 and final degree marks, the magnitude of the correlation decreases with increasing A-level tariff. It was also found that, contrary to anecdotal evidence, there is no link between A-level maths or chemistry and degree success in biosciences. However gender was found to have a marked effect on degree success independent of A-level tariff. Female students consistently obtained marks more than one third of a degree classification higher than male students with equivalent entry qualifications. These results are compared to investigations in other disciplines, notably medicine, and in the context of the drive to increase entry tariff to allow unrestricted recruitment of the top students. (Contains 2 figures, 1 footnote, and 6 tables.)

Context-based chemistry education aims to improve student interest and motivation in chemistry by connecting canonical chemistry concepts with real-world contexts. Implementation of context-based chemistry programmes began 20 years ago in an attempt to make the learning of chemistry meaningful for students. This paper reviews such programmes through empirical studies on six international courses, "ChemCom" (USA), "Salters" (UK), "Industrial Science" (Israel), "Chemie im Kontext" (Germany), "Chemistry in Practice" (The Netherlands) and "PLON" (The Netherlands). These studies are categorised through emergent characteristics of: relevance, interest/attitudes/motivation and deeper understanding. These characteristics can be found to an extent in a number of other curricular initiatives, such as science-technology-society approaches and problem-based learning or project-based science, the latter of which often incorporates an inquiry-based approach to science education. These initiatives in science education are also considered with a focus on the characteristics of these approaches that are emphasised in context-based education. While such curricular studies provide a starting point for discussing context-based approaches in chemistry, to advance our understanding of how students connect canonical science concepts with the real-world context, a new theoretical framework is required. A dialectical sociocultural framework originating in the work of Vygotsky is used as a referent for analysing the complex human interactions that occur in context-based classrooms, providing teachers with recent information about the pedagogical structures and resources that afford students the agency to learn. (Contains 1 table.)

A laboratory experiment currently used in an undergraduate physical chemistry lab to investigate the rates of crystallization of a polymer is described. Specifically, the radial growth rates of typical disc-shaped crystals, called spherulites, growing between microscope glass slides are measured and the data are treated according to polymer crystallization theory. The polymer used is a commercially available poly(ethylene glycol). Effects of molecular weight and crystallization temperature on the growth rate are demonstrated. Background information for students and instructor, experiment procedure, and full analysis of students' results are included in the Supporting Information. (Contains 5 figures.)

This article presents a guided-inquiry (GI) hands-on determination of Fe in food samples including plantains, spinach, lima beans, oatmeal, Frosted Flakes cereal (generic), tilapia fish, and chicken using flame atomic absorption spectroscopy (FAAS). The utility of the GI experiment, which is part of an instrumental analysis laboratory course, considerably motivates underrepresented minority students, enhances student learning, and improves student critical-thinking and problem-solving ability. In addition, hands-on experience using atomic absorption spectrometry for food analysis allows students to better understand the principles and practical operation of FAAS, which they have previously learned in the instrumental analysis lecture course. The students particularly liked working as teams on their food analysis project. Furthermore, the GI food analysis experiment strategy significantly improves the overall student success rate in and enthusiasm for the instrumental analysis laboratory course, facilitating overall student success in the course. (Contains 3 tables and 3 figures.)

One of the biggest challenges for instruction in large-enrollment introductory courses is identifying points of student confusion. One technique that is used to address this problem is the muddiest-point card. However, this technique is logistically difficult to implement in large classes. Personal response devices (or clickers) can be used to facilitate this technique. Instead of providing students a blank card, students are asked to identify their "muddiest point" from an instructor-provided list of topics covered in that day's class. The use of clickers allows students to maintain the anonymity normally associated with the cards used in the traditional implementation. Incorporation of muddiest-point questions into the first and second terms of a general chemistry course is described. About three-quarters of the students who answered other clicker questions during class also answered the muddiest-point clicker question at the end of class. While approximately 75% of the muddiest-point topics were conceptual in nature, quantitative topics were more likely to be chosen as the muddiest point. (Contains 3 figures.)

In a large enrollment, multiple-section course, review sessions enable efficient and consistent delivery of information to all students. A redesigned review session has been implemented to increase attendance and improve effectiveness. The new design involves a practice quiz consisting of about 20 multiple-choice questions that students answer during the review session. These answers are displayed using personal response devices, and the results determine how much time is spent reviewing the solution. The review session questions and answers are then posted to the course website. The attendance has increased from about 5% to over 30%. There is also evidence that the review sessions help improve student exam performance. Students who attended all review sessions were more likely to earn higher grades in the course. Comparison of placement exam scores as a function of the number of review sessions attended indicates that students of all levels attended the review sessions. Students who attended the review sessions and/or viewed the material online scored significantly higher on the corresponding exams than students who did not utilize these supplemental materials. (Contains 5 tables and 3 figures.)

Nationally and internationally, context-based programs have been implemented in an attempt to engage students in chemistry through connecting the canonical science with the real world. In Queensland, a context-based approach to chemistry was trialled in selected schools from 2002 but there is little research that investigates how students learn in a context-based setting. This paper presents one significant finding from an ethnographic study that explored the learning that occurred in an 11th grade context-based chemistry classroom in Queensland. The study found that by providing students with the opportunity to write, fluid transitions (or "to-ing" and "fro-ing") between concepts and context were an outcome of context-based learning. (Contains 4 tables and 1 figure.)

The use of personal response devices (or "clickers") in the classroom has increased in recent years. While few quantitative studies on the effectiveness of clickers have been published, it is generally reported that clickers have been well-received by the students who use them. Two separate populations (Winter 2006 and Spring 2006) of engineering students were given clickers to use during a general chemistry class. Clicker use was compared to student grades for each course. During both terms, a higher percentage of female students than male students "actively participated" in the lectures, where active participation was defined as answering more than 75% of the clicker questions over the course of the term. Active male students earned final grades about 10 points higher than non-active male students. Active female students, however, scored only about 5 points higher than non-active female students. Student learning was assessed by comparing performance on exam questions and clicker questions with similar content. Students who answered clicker questions correctly were 11-13% more likely to answer the corresponding exam questions correctly than were students who did not answer the clicker question. In this paper, we demonstrate the effectiveness of clicker use in the classroom and examine gender differences associated with this use.

The purpose of this study was to evaluate the instructional effects of using animations, static figures, PowerPoint bulletins, and e-plus software as chemistry texts with the aid of computer-based technology. This study analyzed the characteristics of students involved in three multimedia courses and their achievement and attitude toward chemistry and learning chemistry. The three samples included in this study involved 257 undergraduate engineering students enrolled in the courses during the academic year in which the study occurred. The results indicate that: (a) students acquired a better understanding of targeted chemistry concepts during the multimedia courses, (b) some categories of students, based on their major area of study, computer use, and attendance status at orientation achieved significantly (p less than 0.05) higher post-test scores when adjusted for pre-test performance, and (c) significant differences and Cohen's effect sizes in attitudes toward chemistry and learning chemistry were detected for students' level of computer use, disposition toward computer multimedia, gender, and attendance at the multimedia orientation session. It appears to be helpful to incorporate computer-based multimedia (animations, images, sounds) teaching while utilizing constructivist design principles to facilitate students' chemistry understanding and attitude toward chemistry and learning chemistry.

Even though several studies have reported positive attitudinal outcomes from context-based chemistry programs, methodological obstacles have prevented researchers from comparing satisfactorily the chemistry-learning outcomes between students who experience a context-based program with those who experience a content-driven program. In this narrative inquiry we are able to address the question: how do the recalled experiences of a student and her teacher in context-based and concept-based chemistry programs compare? From the student's unique perspective of experiencing both programs with the same teacher, we have constructed our collective account around four themes; namely, the extent to which the student makes connections between chemistry concepts and real-world contexts, developing research independence through engaging in extended experimental investigations related to contexts, learning chemistry concepts through contexts, and conceptual sequencing in a context-based program. The student reported real-world connections between chemistry concepts and contexts, found her engagement in the context-driven tasks interesting and productive, and identified connected sequences of concepts across the contexts studied. Despite difficulties for teachers who are required to shift pedagogies, the student's lived experiences and outcomes from a context-based program provide some encouragement in working through these issues.

Various new cell culture experiments for the development of microparticles are conducted. These studies have also led to the development of an anticancer egg, in addition to the analysis of various vegetable soup chemical reactions.

The presence of cultural basis within undergraduate general chemistry textbooks is examined by assessing the extent to and manner in which people of color are represented in textbook photographs. It is proposed that the images that students look upon in the textbooks help in their perceptions of chemistry as a whole.

The impact of biodiesel on classrooms and teaching laboratories has potential similar to country's energy security and could help introduce environmental concepts, thermodynamics, titrations, combustion and chemical reactions. While researchers are exploring new methods and approaches to alternative fuels and renewable energy, the educators could do their job by ensuring that the education system produces citizens who are aware of the need for alternative energy sources.

The research advances made in chemosensors, tracking Dragon's blood, anthrax and the renewable source of hydrogen for fuel cells are discussed. The features and the uses are presented.

Abstract Background Combined Heat and Power (CHP) systems can provide a range of benefits to users with regards to efficiency, reliability, costs and environmental impact. Furthermore, increasing the amount of electricity generated by CHP systems in the United States has been identified as having significant potential for impressive economic and environmental outcomes on a national scale. Given the benefits from increasing the adoption of CHP technologies, there is value in improving our understanding of how desired increases in CHP adoption can be best achieved. These obstacles are currently understood to stem from regulatory as well as economic and technological barriers. In our research, we answer the following questions: Given the current policy and economic environment facing the CHP industry, what changes need to take place in this space in order for CHP systems to be competitive in the energy market? Methods We focus our analysis primarily on Combined Heat and Power Systems that use natural gas turbines. Our analysis takes a two-pronged approach. We first conduct a statistical analysis of the impact of state policies on increases in electricity generated from CHP system. Second, we conduct a Cost-Benefit analysis to determine in which circumstances funding incentives are necessary to make CHP technologies cost-competitive. Results Our policy analysis shows that regulatory improvements do not explain the growth in adoption of CHP technologies but hold the potential to encourage increases in electricity generated from CHP system in small-scale applications. Our Cost-Benefit analysis shows that CHP systems are only cost competitive in large-scale applications and that funding incentives would be necessary to make CHP technology cost-competitive in small-scale applications. Conclusion From the synthesis of these analyses we conclude that because large-scale applications of natural gas turbines are already cost-competitive, policy initiatives aimed at a CHP market dominated primarily by large-scale (and therefore already cost-competitive) systems have not been effectively directed. Our recommendation is that for CHP technologies using natural gas turbines, policy focuses should be on increasing CHP growth in small-scale systems. This result can be best achieved through redirection of state and federal incentives, research and development, adoption of smart grid technology, and outreach and education.

Presented is a collection of terms associated with fourier transformations in chemistry. These terms are cross-referenced to a four-part article in the "Journal of Chemical Education." (CW)

Described are six multipulse experiments with an emphasis on their application to common problems in chemistry. Exercises in relaxation time measurement, spin echoes, and polarization transfer are proposed. (CW)

Examined are some of the types of two-dimensional spectra. Their application to nuclear magnetic resonance for the elucidation of molecular structure is discussed. Included are J spectroscopy, H-H correlation spectroscopy, heteronuclear correlation spectroscopy, carbon-carbon correlation, nuclear Overhauser effect correlation, experimental considerations, and three-dimensional NMR. (CW)

A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives results that are comparable to those of a more expensive commercial carbon electrode. The level of vitamin C measured was higher than the daily intake recommended by Health Canada and the United States Food and Drug Administration, which is 60 mg/day for a healthy adult. The detection limit of the pencil lead electrode was also determined. (Contains 1 table and 4 figures.)