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In this study, we analyzed how scientific terms such as principle, law and theory are depicted in Chemistry textbooks used by students in Singapore. There are very few reports in the science or chemistry education literature that explicitly explore the term principle, although all three terms appear in a number of topics in the high school chemistry curricula. The textbooks' definitions for the three terms were compared with key canonical attributes constituting these general terms. Findings indicate that most of the textbooks did not provide generic definitions of the three terms, and a number of attributes were also not apparent in the specific definitions of the three terms (except for principle). The relationship between laws and theories in textbooks was explored for three exemplars, and this provided useful insights. It is suggested that textbook authors, supported by curriculum developers and teachers, devote more attention to highlighting the relationships and distinctions among the three scientific terms. This can help students cultivate a better understanding of these terms, thus potentially leading to improved overall understanding of the nature of science.

Plant-derived natural products are an important source of potential medicines and continue to have a major impact on the drug discovery process. Natural product discovery assignments provide an opportunity to present various experimental techniques to undergraduate students in introductory medicinal chemistry. This assignment was developed to serve as a meaningful hands-on exercise to introduce undergraduate Chemistry students to the common procedure in the early phase of drug discovery using inexpensive corn silk, in which the final year undergraduate student used Recycling Preparative High-Performance Liquid Chromatography to separate and purify steroids from corn silk. The student used advanced spectroscopic methods such as UV, IR, and one- and two-dimensional NMR to elucidate the structures of these steroids. The cytotoxic activity of these steroids was also evaluated and found to be non-cytotoxic to normal human MRC-5 cells at 60 µg/mL via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. With this assignment, students gain meaningful multidisciplinary hands-on exercises with the common procedure in the early stages of drug discovery and understand the process of isolating natural compounds that may lead to the development of new drugs.

The main aim of this study is to examine the measurement invariance of the structural equating model constructed on the Awareness and Exposure subscales of Nanoscience and Nanotechnology Awareness Scale (NSTAS) test for three teacher branches, three school types, and two genders by using the covariance structural analysis to test configural and metric invariances. The other aim of this study is showing how to use the IBM AMOS-24 software package with examples to address the issue of measurement invariance using the covariance structural analysis approach. Study sample was 1039 complete records gathered from science teachers with convenience sampling. Research data were collected in two stages. In the first stage, data were obtained from 624 teachers who participated to the study in the 2015-16 academic year. In the second stage, data were obtained in 2019 from 415 teachers via a link to access to the scale and all the instructions for the NSTAS in 2019. The covariance structures analysis was used to examine the measurement invariance of the scale. The comparative fit index was used to compare the measurement invariance in the measurement model. The study revealed that configural, measurement weight and structural covariance invariances were ensured for branches, school types and genders. Residual invariance was ensured only for gender. As a result, it was concluded that the NSTAS scale was not biased for teacher branches, school types or gender. NSTAS scale is recommended for the purposes of comparing branch, school type and gender groups. [Paper presented at the International Congress on Measurement and Evaluation in Education and Psychology (6th, Prizren, Kosovo, September 5-8, 2018).]

A variety of strategies have been introduced to tackle the issue of laboratory safety in academic settings. These strategies include innovative educational tools as students transition from the classroom into the laboratory, the introduction of policies designed to protect the researchers in the laboratory environment, and the creation of teams of peers at the departmental level that focus on creating a culture of safety. We recently developed, as a training exercise, virtual reality (VR) modules that replicate the visual and auditory complexities of authentic research laboratories ( J. Chem. Educ. 2022, 99, 1982-1989). We have now used the VR environments to compare the relative abilities of individuals and of teams to identify laboratory hazards by quantifying several variables: time spent in the virtual environment, percentage of total hazards identified, percentage of hazards correctly characterized, number of attempts to identify hazards, and number of requests for assistance. In addition, an online survey was used to assess the perceptions of individual and team performances by the participants. Quantitative measures demonstrated the superior performances of teams versus that of individuals. Intriguingly, the smaller coefficient of variance associated with these metrics for teams (versus individuals) implies a group dynamic that suppresses outliers. Finally, results from the online survey reveal that the team format is perceived to be more effective than individuals in identifying hazards. However, team leaders were more subdued in their enthusiasm for the group format than were the members of their teams, which appears to be associated with subtle group dynamics.

The preparation of ethyl acetoacetate is a distinctive, century-old classic organic chemistry laboratory project. Ethyl acetate and sodium metal (sodium ethoxide) are reacted by Claisen ester condensation to produce the sodium salt of ethyl acetoacetate and then obtain the refined product by acidification as well as washing, drying, and distillation under reduced pressure. This article analyzed the reasons for the low product yield and poor purity of the traditional experimental method and found that ethanol was the key to the final product. The improved experimental method used rotary evaporation and washing with saturated calcium chloride solution to remove ethanol. The new experimental method not only retains the characteristics of the original experiment and improves the product yield, but also adds the interesting phenomenon of pointing water into "ice", which cultivates students' learning interest and innovation and achieves a good teaching effect.

Active learning, a common practice in higher education, has been shown to promote higher order thinking and skills. Class discussions have been chosen to be the medium to incorporate active learning in schools' curriculum. However, the rate of class participation could be low for certain courses. Literature has shown that the fear of negative evaluation from peers is the most common reason as to why students choose not to partake in class discussions. Anonymity via clickers or applications such as "Kahoot!" has shown to be useful in reducing students' anxiety and increasing class participations. However, this is not a viable method to employ if vocal discussion is required for the course. Here, partial anonymity (voice only), Speak Your Mind, was applied into an environmental chemistry course with 20 students in the National University of Singapore (NUS) to study its correlation with students' anxiety and class participation. Participants survey results suggested that a reason for not participating in class discussions was the fear of being judged by their peers. Remote learning was conducted due to COVID-19 and partial anonymity was obtained by a proxy application: Clubhouse. This application allowed students to partake in a podium discussion while maintaining psychological safety via partial anonymity. Participants survey responses indicated that partial anonymity reduced their anxiety (Cohen's d = 0.58) and slightly increased their self-reported class participation rate (Cohen's d = 0.21); it was noted that partial anonymity did not have much effect on their fears of being judged if they provided the wrong answer (Cohen's d = 0.11).

Knowledge related to photochemistry has been gradually introduced as a part of chemistry courses at both undergraduate and postgraduate levels. However, due to their complex conceptual principles, limited class time, and tedious experimental setup and methodologies, students tend to encounter difficulties in understanding the concepts and comprehending the applications of fluorescence in their daily lives. Hence, developing effective multidisciplinary approaches to help students understand such intricate and complicated concepts remains a focus for most chemistry educators. In this study, we demonstrated the introduction of the excitation-emission matrix and how it can be used to monitor the effect of thermal treatment on different olive oils via the fluorescence fingerprinting method. The heating effect on the fluorescent properties of three olive oils, including extra virgin olive oil, refined olive oil, and blended olive oil, was discussed in a multidisciplinary approach that incorporates mathematical analyses. A speed-reading-based informative questionnaire survey was also conducted on students to investigate whether this method was effective in aiding students to better understand the physical significance of the excitation-emission matrix and its relevance to their daily lives. The acceptability and extensibility of this method were further evaluated by the student's performance in this survey.

For chemistry, where learners are required to integrate experimental observations with theoretical knowledge, laboratory work appears to be a viable instructional strategy. However, research has shown that chemistry laboratory instruction often fails to live up to its potential. The scheduling practice in higher education (HE) separating theory lessons and practical work into temporally disjointed sessions could exacerbate the theory-laboratory disconnect. This paper continues an earlier work, in which integrated schedules of chemistry tutorial and laboratory classes were implemented in two general chemistry courses in a freshman chemical engineering programme. Traditionally separate tutorial and laboratory classes were chained into 3 hour blocks in the experimental classes. Worked examples, group presentations and course materials designed as a merged package to connect theory with practical work were implemented for selected tasks in integrated teaching. Prior ability was measured based on previous titration experience or grades in earlier general chemistry courses. Lesson experiences were collected on the validated Meaningful Learning in the Laboratory Instrument (MLLI) (Galloway and Bretz, 2015). Block (or integrated) and traditional learners performed equally on theory tests, but integrated learners scored higher on a titration skills assessment. The origin of differences in skills performance could not be ascertained conclusively. Perceptions across the MLLI domains declined across schedules, with significant losses in the cognitive domain. MLLI scores did not differ by schedules. There is some evidence favouring stronger theory-laboratory connection from the qualitative MLLI data and the focus group interviews, although cognitive overloading may adversely impact low ability learners. This work showed that block scheduling does not affect the chemistry skills-set equally, which opens the topic for future research. Suggestions for future implementation of chemistry block teaching were also proposed.

The aim of this study was to determine the validity and reliability of the Nanotechnology Awareness Scale (NAI) in Turkish culture. The study group consists of 624 biology, physics and chemistry teachers working in secondary schools in Antalya, Denizli, Burdur and Ankara. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were conducted in order to determine its structural validity. Cronbach-alpha and stratified-alpha coefficient values were calculated for the reliability of the sub-dimensions and the whole of the scale, respectively. In EFA, Kaiser-Meyer-Olkin (KMO) value was found to be 0.92 and the Bartlett Test result (912 91 = 6519.27, p <0.00) was found significant. In addition, in original scale, a two-factor structure was found. This two factors solution explains 59.192% of the total variance. In CFA, factor structure of the scale was tested for two-factor solution as it was designed. According to the findings, it was found that the scale, containing 14 items with two sub-dimensions, had sufficient goodness of fit indices such as X[superscript 2]/sd =1.344, RMSEA = 0.07, GFI = 0.97, CFI = 0.97, NFI = 0.90 and AGFI = 0.83. These goodness of fit indices shows that we have good model-data fit. The Stratified-alpha coefficient was found as 0.942 for the whole scale. Cronbach alpha coefficient was found as 0.935 and 0.805 for the awareness sub-dimension and exposure sub-dimension, respectively. As a result of the research, it was concluded that the Turkish version of the scale can be used as a valid and reliable measurement tool.

To develop expertise, novice chemistry students require deliberate practice with immediate and thoughtful feedback. Whereas opportunities for practice are often abundant, opportunities for feedback tend to be much scarcer. To address this challenge, we collaborated with students to develop a flexible and scalable online platform called "Alchemy." Students interact with the software through a series of prompts and multiple-choice questions, receiving targeted feedback at each step. Each student can navigate a scenario differently, influenced by their prior knowledge and misconceptions. In design, scenarios are instructor-created graphs that model their expert-level thought process­(es) and teaching experience. This graph format is a distinct and advantageous feature of Alchemy that supports linear, nonlinear, and cyclical progression through a concept or problem. Alchemy-based homework has been assigned in lecture and lab courses, at the sophomore and junior levels, with enrollments ranging from many tens to many hundreds of students. Approximately 80% of students rated Alchemy as very/extremely helpful to their learning, emphasizing the value of the step-by-step process and feedback. Alchemy is discussed in the contexts of other software platforms, its advantages and limitations, lessons learned in its initial deployments, and future directions for its development and usage.

The chirality of chemicals is a well-known concept among undergraduates. The examples of chiral molecules in daily life are introduced to high school students as well. However, the chirality of single-walled carbon nanotubes (SWCNTs) remains unpopular in these groups. In this paper, a simple visualization of SWCNTs was first performed via paper origami. Then, a cost-effective separation experiment was introduced to the students to achieve the actual chiral SWCNTs. The proposed visualization and separation of chiral SWCNTs were evaluated in students' science projects. Introducing the chirality concept to students would enhance the students' understanding of nanomaterials and the chirality of SWCNTs.

To gauge the variability in expert problem-solving strategies for stoichiometry problems, a set of experts in different career tracks were studied with the cohort including 17 graduate students in chemistry, three college chemistry instructors, and seven college graduates working in the industry. The goal of the study was to determine whether variability would be observed based upon experience and career trajectories. The data were collected using interviews and analyzed qualitatively and quantitatively using the COSINE (Coding System for Investigating Sub-problems and Network) method. Although the method was developed for the analysis of undergraduate problem-solving, it appeared to be effective in examining experts' problem-solving in chemistry as well. The study revealed similar abilities for succeeding at solving a series of problems, but the strategies were variable for the three cohorts of experts. Specifically, the amount of information used to solve the problems differed across the three cohorts with graduate students focusing more upon each of the specific subproblems within each problem compared to industry chemists utilizing the big-picture approach in lieu of breaking down each problem into respective subproblems. Familiarity with the question types and ability to chunk information were common characteristics observed consistently for the expert participants, which is consistent with existing research.

Online multiple-choice instruments to diagnose students' understanding of science concepts are easily developed and administered to students using Google Forms. This article describes a web-based three-tier multiple-choice test for the formative assessment of students' understanding of chemical bonding. The results obtained can lead to follow-up discussions with students if they have difficulties with the concepts involved.

The science laboratory is a politically entrenched space where complex power relations interplay while social agents learn about the rules and routines to ensure safety, precision and reproducibility in research work. This paper presents a case study of two Singaporean students undergoing apprenticeship in a 3-year school-based School Scientist Programme. They engaged in an open and authentic science inquiry involving chemical synthesis in the school's science laboratory under the apprenticeship of an in-house School Scientist who started the programme. The goals of this paper are to offer an alternative--critical and nuanced--lens to the dominant positivist and social constructivist discourse about science research apprenticeship. Using visual ethnography approach, we collected videos and photographs of the students' and School Scientist's interactions during the science research over the first 18 months of the programme. The study documented critical events that showed shifts in control over knowledge construction and mastery of the chemical synthesis craft as the science research progressed. This paper contributes to the Foucauldian theory of power in offering an alternative view to the dialectical explanation of power and knowledge. First, it shows that while there is an overall gain in knowledge of chemical synthesis increased during the apprenticeship, the power relationship fluctuates when a different genre of chemical synthesis work was introduced. The fluctuation is related to the overtaking and relinquishing of control (power) with the latter leading to the construction of knowledge. Second, we show how the power relationship, involving the interplay of power and knowledge between the expert and apprentice, is more interconnected and complex. The findings of this study have implications for teachers who want to plan and enact authentic science inquiry with their students.

As numerous varsity campuses remain closed during the coronavirus disease 2019 pandemic, educators must look for suitable digital tools to conduct lessons and engage learners online. In this report, we discuss how to structure the online lessons using the Community of Inquiry framework (CoI). The CoI was applied to the university elective course "Learning to Choose Better", taught by chemistry faculty. By using the appropriate digital tools in our course, we found success in achieving engagement, active learning, and team teaching. Until the world finds a resolution to the pandemic, online teaching will continue to be the new normal. Educators could view this time as a prime opportunity to experiment, innovate, and break new grounds in the realm of remote online teaching.

The advance of digital technology presents an opportunity to equip students with relevant skill sets as "Scientists of the Future" who are able to utilize knowledge at the interface between various disciplines. In this technology report, an open source programming language is used to automate a simple laboratory experiment commonly performed by Chemistry and Chemical Engineering students. It is introduced and demonstrated to the students from a 3-year Chemical Engineering undergraduate program. The aim of this activity is to allow students to appreciate the integration of knowledge from Chemistry and Computer Science.

In this study, we reviewed 76 journal articles on employing drawing assessment as a research tool in science education. Findings from the systematic review suggest four justifications for using drawing as a type of research tool, including assessment via drawing as (a) an alternative method considering young participants' verbal or writing abilities, and affective or economic reasons, (b) a unique method that can reveal aspects not easily measured by other methods, (c) a major method that reflects characteristics of science subjects, and (d) a formative assessment to diagnose students' ideas to benefit their learning. Furthermore, five research trends of studies using drawing as assessment tools are identified, including: (a) students' conceptions of scientists from the Draw-a-Scientist-Test (DAST) and evolving studies, (b) students' understanding or mental models of science concepts, (c) participants' conceptions of science learning or teaching, (d) students' inquiry abilities and modelling skills via drawing, and (e) technology to support drawing. For each trend, we synthesised and commented on the current findings. A framework conceptualising phases and issues when designing research and instruments employing drawing assessments is proposed. The review provides insights into the design and future direction of research employing drawing assessments in science education.

Advances in nanotechnology have drawn attention to nanotechnology education. The aim of this study is to determine awareness, exposure, and knowledge levels of science (physics, chemistry and biology) teachers about nanoscience and nanotechnology. Teachers (N=624) from secondary schools in Turkey comprised the working group. Descriptive methods were used in data analyses. Awareness and exposure subscales were adopted from the "Nanotechnology Awareness Instrument" developed by Dyehouse et al. (2008), and the knowledge subscale, developed by the authors, was added to the Turkish version. Differences among or between the teachers' awareness, exposure, and knowledge levels regarding nanoscience and nanotechnology were determined. No significant differences were found in levels of awareness, exposure, and knowledge of teachers in terms of subject specialisation and educational levels; however, some significant differences were found in gender, tenure, grade and type of school, in-service training participation, following scientific publications, documentary watching frequency and school localisation variables. In general, nanoscience and nanotechnology awareness, exposure, and knowledge levels of the teachers were at a "neutral" level. This study shows needs for further training of science teachers in nanoscience and nanotechnology, to increase their level of awareness and knowledge and to ensure their preparedness for teaching this topic.

The authors developed a lesson for teachers to integrate chemistry and culinary arts, providing students with an opportunity to participate in three-dimensional learning, engage in science and engineering practices, and apply disciplinary core content and crosscutting concepts (Krajcik et al. 2014). The project involved five classes: three integrated chemistry and physics (ICP) classes and two culinary arts (CA) classes, with mainly sophomores and juniors. The lesson was part of a larger interdisciplinary project involving multiple classes working together to develop a gingerbread house community with an interactive light and music show. The ICP students' task was to design a window panel on a gingerbread house out of candy with optimal transparency and provide data-driven recommendations to CA students for the proportion of sugars to use in the candy recipe. Students learned about the structure and properties of key components of candy (glucose and sucrose) and how the proportion of glucose and sucrose in the mixture affects the molecular structure, transparency, and hygroscopicity. (A hygroscopic substance is one that readily attracts water through its surroundings, through either absorption or adsorption. Hygroscopicity is the percentage of moisture on the surface.) This article describes the project with particular attention to the teacher scaffolding of the inquiry and examples of student artifacts.

The internet is prevalent in society today, and user-friendly web-based productivity tools are readily available for developing diagnostic instruments. This study sought to determine the affordances of a web-based diagnostic instrument on ionisation energy (wIEDI) based on the pen-and-paper version, the Ionisation Energy Diagnostic Instrument (IEDI) that was previously developed and reported on. The Google Forms platform was used to develop the wIEDI and it allowed a degree of personalisation such that specific second-tier options are offered in response to the student's choice of answer in the first tier. Students could choose one or more reasons in the second tier or supply their own reasons, and they were asked to indicate their confidence in their choice of answer-reason combinations. The wIEDI was administered to 274 A-level students (257 Grade 11 and 17 Grade 12), and answer-reason combinations indicating alternative conceptions were highlighted only if 5% or more students expressed confidence in them in the third-tier confidence measure. The results showed that all the possible alternative conceptions of ionisation energy reported in the previous study were also identified in the present study. Additional alternative conceptions were indicated as new reasons had to be developed for many items in the wIEDI to ensure that there were sufficient reasons for each first-tier response, and students were allowed to choose more than one reason for their answer. The wIEDI better facilitated responses reflecting the consistency of the use of specific ideas in student thinking and provided direct evidence of students' possible manifold conceptions and thinking within each question as well as across a range of questions. It also allowed easy collation of the comments students typed in response to the 'Others' and 'I do not know the answer' options. Thus, the study makes a case for researchers and teachers using such technology in the diagnostic assessment of students.

Traditional modes of chemistry education in schools focus on imparting chemistry knowledge to students via instruction. Consequently, students often acquire the mistaken understanding that scientific knowledge comprises a fixed body of "proven" facts. They fail to comprehend that the construction of scientific understanding is a human and social endeavor. Consequently, there can be alternative and conflicting views and theories. To provide students access to an enhanced learning curriculum, Legends of Alkhimia was designed and developed as an educational game for 13 to 14-year-olds to foster the learning of chemistry through inquiry. The multiplayer game supports four concurrent players. It is played on personal computers connected via a local area network. The game embeds students in problem solving challenges related to the use of chemistry in realistic contexts. In attempting to solve these problems, students must engage in individual laboratory work using an in-game virtual chemistry lab. The game levels take students through a narrative arc that provides coherence to the entire gameplay experience. Legends of Alkhimia, together with its associated curricular materials, instantiates classroom learning based on performance pedagogy: a pedagogy that constructs learning through the lens of performance theory. Leveraging the immersive affordances of 3D game environments, the learning experience is designed to engage students in the dialectic interplay between learning in the first person, based on playing the game, and learning in the third person, based on the Bakhtinian notion of dialog. The learning process follows a developmental trajectory of becoming a chemist. Enacting performance pedagogy in the classroom requires a shift in traditional classroom culture toward that of a professional practice community. We report on an empirical study of a game-based learning classroom intervention where students in the Alkhimia learning program participated in an 8-week curriculum sequence involving six levels of game play. We compared pre- and posttest survey responses from a class of 40 students who learned chemistry using the Alkhimia curriculum. We also compared learning outcomes of students in the said intervention class with a control class of 38 students who learned chemistry through traditional classroom instruction. All students in our study were 13-year-olds from a typical government secondary school. We noted significant shifts in intervention students' perceptions of their identity, their epistemological beliefs, their dispositions toward science inquiry, and of classroom culture. Students' understanding of chemistry was evaluated through a common assessment that comprised a complex separation task involving mixtures, solutes, and immiscible liquids. Two evaluation criteria were used: (1) effectiveness of separation, and (2) demonstration of conceptual understanding of chemistry. We found that the Alkhimia students significantly outperformed the control students when assessed on the extent to which effective separation was achieved in the students' proposed solution (t75 = 2.56, p = 0.026) and when assessed with respect to conceptual understanding of chemistry in the separation task (t75 = 3.41, p = 0.002). We discuss, from a theoretical perspective, how and why learning with the Alkhimia curriculum is efficacious. Our findings are significant in that they suggest how inquiry learning can be successfully enacted in a chemistry game-based learning curriculum, and they underscore the efficacy of approaching game-based learning in terms of performance. (Contains 1 table and 4 figures.)

There is a need for schools to engage students in constructing scientific theories like practicing scientists in order to excel in the 21st century knowledge economy. An approach to engage students in constructing scientific theories is to enculturate students in doing science with language, which differs from the mainstream classroom discourse--talking about science. In terms of doing science with language, young people use language to produce scientific knowledge like practicing scientists. When it comes to talking about science, students learn to master science knowledge constructed by scientists, eventually leading to a positivist epistemology and consumer identity. In this paper, we conceptualize an approach to design science classroom discourse toward doing science and instantiate the conceptualization with a game-based learning program. The result is eight two-hour sessions chemistry program that is revolved around a six-level role-playing computer game--the "Legends of Alkhimia". (Contains 2 tables and 1 figure.) [This research is supported by a grant from the National Research Foundation/Ministry of Education IDM (Interactive Digital Media) Projects in Singapore.]

A hands-on design activity named "electrochemistry designette" that incorporates design thinking with the aims to strengthen electrochemistry concepts, introduce prototyping ideas, encourage student class participation, and foster creativity is presented. This active learning activity, which lies at the interface of design and electrochemistry (mixed methods approach), allows students to experience "design thinking" as a creative tool through the application of electrochemical principles. The "designette" permits the students to design and prototype, from an available design prototyping kit, a 6-cell electrochemical device capable of turning on 4 light-emitting diodes (LEDs). The electrochemical device consists of electrode pairs composed of Cu, Zn, Al, and Sn electrodes, along with rice wine and CuSO4 solution as electrolytes, connected via staples, wires, and eyelets. The designette allows for the direct and objective evaluation of students' performance via three critical parameters: the number of prototypes created, the power harnessed by the voltaic device, and the number of total LEDs powered on by the device. The effectiveness of the designette as a pedagogical tool for design-based learning (DBL) was evaluated through pre- and post-designette electrochemistry tests. Generally, results show that the designette improves the student's ability to recall information, therefore enhancing the learning experience of the students. Students who participated in the designette displayed statistically significantly higher scores in the electrochemistry assessment after the designette. Furthermore, we found some evidence between performance in the designette and post-designette creativity. Interestingly, no correlations were found between performance in theoretical quizzes, designette performance, or pre-designette creativity metrics. The "electrochemistry designette" can be carried out as an activity in a chemistry course or a workshop on "design" for high school students with a background in electrochemistry, for undergraduate engineering and architecture students, and for general undergraduate students enrolled in an introductory general science course, independently of their interest in "design."

Key to renewed concern on the affective domain of education (Fensham, 2007) and on school graduates' readiness for a world of work (DEST, 2008; WDA, 2006) is the student's inclination-to-reflect when engaged in a learning or problem-solving task. Reflective learning is not new to education (Dewey, 1933; Ellis, 2001). Since the inclination-to-reflect may not be obvious even among adults at work (Seibert & Daudelin, 1999), how much more can we expect from school students? This article presents part of a research on secondary school students' inclination-to-reflect when engaged in chemistry learning tasks. The instrument used is the three-part Chemistry Learning and Thinking Instrument (CLTI). The first part seeks to characterize students' inclination-to-reflect while attempting chemistry learning tasks and the other parts aim to characterize their learning-thinking preferences in the subject. This article shares the construction of the learning tasks in the first part and how students' reflective responses to these tasks are encouraged, scored and analyzed. Since assessment is said to drive teaching and learning, an alternative form of assessment, such as these CLTI items, may help students become more reflective in their learning habits and hence more adaptable to the world of work. (Contains 1 table and 5 figures.)

Three internally developed mobile apps, "3D Sym Op", "SM2 Chem" and "ARMolVis," available for free on both the Apple App Store and Google Play Store were evaluated in seven studies. Each study was a systematic process of Pre-Test, In-lecture App Demo, App Assisted Interactive Tutorials (AAITs) and/or Independent App Usage (IAU), followed by a Survey and Post-Test. Overall, the mobile apps were effective evident by the higher Post-Test vs. Pre-Test % increase for those who used the app more frequently compared to those who used the app rarely. Apps were most effective when used in AAITs with the Blended Learning approach. This approach requires the physical presence of both teacher and student, but with some element of student free play such as using the app to complete worksheets in pairs or groups.

The handling of chemicals in the laboratory presents a challenge in instructing large class sizes and when students are relatively new to the laboratory environment. In this work, we describe and demonstrate an augmented reality colorimetric titration tool that operates out of the smartphone or tablet of students. It allows multiple students to conduct the exercise at the same time, respond quickly to actions made, and correctly depict the colors associated with changes in pH values for the indicator used. The tool imbues unparalleled realism in the conduct of the experiment and offers to strongly help students acquire bench skills with minimal use of liquid chemicals, thereby reducing handing risks for them and resulting in lower negative impacts on the environment. The feedback received from undergraduate students that participated in an initial small test exercise with the tool corroborates this.

This study examines the verbal interactions among a group of pre-service teachers as they engaged in scientific discussions in a medicinal chemistry course. These discussions were part of the course that encompassed an explicit instruction of scientific argumentation structures as well as an applied component, whereby the pre-service teachers learned the content of medicinal chemistry through cases developed using the strategy of competing theories. By adopting a case study approach using sociocultural framework of learning, we examined the interactions between the pre-service teachers using video data. We describe 12 possible forms of interactions during discussions--(1) seeking clarification, (2) figuring out loud, (3) sharing information, (4) agreement, (5) asking questions, (6) providing explanations, (7) raising strategic and procedural issues, (8) stating claims, (9) disagreement, (10) sharing perspectives, (11) offering alternatives, and (12) persuasion. The pre-service teachers engaged in figuring out aloud and seeking clarifications frequently, and used persuasion least in their discussions. To clarify their ideas and thoughts, pre-service teachers commonly rebut their counterparts and used warrants to support their own assertions. A similar pattern was also observed when figuring their thoughts out loud. Our findings suggest that pre-service teachers were able to carry out rebuttals in the argumentation process. However, the quality and function of their rebuttals can be improved by deepening their understanding of the subject matter knowledge and the science argumentation structure. Implications are discussed.

In this paper, we define flip teaching as a curricular platform that uses various strategies, tools, and pedagogies to engage learners in self-directed learning outside the classroom before face-to-face meetings with teachers in the classroom. With this understanding, we adopted flip teaching in the design and enactment of one Year 1 and one Year 2 undergraduate chemistry laboratory session at a higher education institution. The undergraduates viewed videos demonstrating the practical procedures and answered pre-laboratory questions posted on the institution's mobile device application before the laboratory lessons. Analyses of the lesson videos, interviews with the undergraduates and instructors, and undergraduate artefacts showed that the undergraduates had developed a better understanding of the theory undergirding the procedures before they performed the practical, and were able to decipher the complex practical procedures. They also experienced less anxiety about the complex practical steps and setup, and subsequently, improved work efficiency. The findings of this study have implications for chemistry educators looking for ways to improve on the design and enactment of the laboratory curriculum to enhance the undergraduates' self-directed learning.

In classrooms, science is usually taught within the cognitive domain while the psychomotor learning domain is achieved through performing science experiments in the laboratory. Although students attend civic and moral education and pastoral care classes where values and life skills are often taught directly, learning experiences in most school subjects such as science are still centred on preparing for high stakes examinations. It is therefore not surprising that affective domain learning outcomes are often the least considered when teachers plan or conduct their science lessons. This paper is a report on three school-based trial lessons in which students from two Singapore secondary schools were taught science concepts and skills in the usual manner with follow-up reflective activities requiring them to draw from their learning experiences parallel scenarios in their daily lives. The students were taught chemistry topics like reactivity of potassium metal (taught to a secondary 4 normal technical class), sedimentation as a separation technique (taught to a secondary 3 express class), and reaction characteristics of weak and strong acids (taught to a secondary 2 express class). At the end of each lesson, students had to discuss, reflect and respond to an everyday event or scenario which has characteristics similar to the chemistry topic or skill they had just learnt. This cognitive-affective integrative teaching approach aims to help students surface important values, positive social habits or effective life skills. Although this is not a research project but an exemplary teaching practice, observations of students' reflective responses to the tasks and feedback on learning experiences from students and teachers show great potential for this teaching approach to be a possible way in helping raise the profile of affective learning objectives in school science lessons.

Background: The development of two-tier multiple-choice questions has permitted the diagnosis of students' understanding on various topics in the sciences as well as helped to ascertain the alternative conceptions they have. A limitation of two-tier diagnostic instruments that has been noted in the literature, but which has not been systematically explored, is that some questions can have a diagonal response. This can allow students to select a second-tier response based on cues from a particular response in the first tier, and it can limit the analytical utility of the diagnostic instrument to some extent. Purpose: The study explores an enhancement of the traditional two-tier diagnostic instrument to address diagonal response. In the format proposed, there are dual sections for both the answer and reason tiers. The answer tier is in dichotomous form and for each of the dichotomous responses, there are separate polytomous responses in the reason tier. Sample: There were 99 students of grade 10 level who participated in this study. Design and Method: The research design follows the usual approach adopted for the development of diagnostic instruments but with some modifications. The topic of electrochemical cells was chosen to evaluate the effectiveness of the enhanced format of the two-tier instrument. Results: It was found that with the enhanced format, the issue of diagonal response has been satisfactorily addressed. Also, a situation where students get the answer wrong but the reason correct, which is sometimes encountered in two-tier questions, does not arise with this format. The instrument has also been able to shed some light on the students' understanding of electrochemical cells and their alternative conceptions. Conclusions: The enhanced format of the two-tier instrument proposed in this study can also be used for the study of alternative conceptions in science education.

This paper examines learning of science in 15 grade nine classrooms by analyzing the type of talk that teachers engaged in. Using transcripts from audio recordings that are part of the Singapore Corpus of Research in Education database, annotations were carried out on the phrases of teacher talk using Mortimer and Scott's framework for meaning making in science classrooms. Interpreted from a sociocultural view of science learning and based on text coverage per 1,000 words spoken by teachers and students, we analyzed the content of instruction and found that (1) teachers in all three sub-disciplines of science used the least number of words to make statements of generalizations, with chemistry teachers privileging description more than physics and biology teachers, while physics teachers use more words for explanation when compared with biology and chemistry teachers and (2) teachers from all three sub-disciplines depended more on empirical justification than theoretical justifications. These findings suggest that most scientific stories in Singaporean grade nine classrooms are dependent on specific contexts and that the nature and organization of knowledge in each sub-discipline defines the features that teachers use in the classrooms to talk knowledge into being. We discuss our findings on whether science curriculum should be framed as "separate subjects" or if they should be developed as "integrated science" and draw implications to science teacher education and the conduct of high stakes public placement examinations.

In response to Goff, Boesdorfer, and Hunter's article on the use of a multicultural approach to teaching chemistry and the nature of science, I forward this critical reflective essay to discuss more general curriculum aspects of the relationship between the nature of science and science education in school contexts. Taking a social realist perspective, I argue for a more nuanced understanding of the role of epistemology and ontology in science classrooms, and for a reconsideration of the role of knowledge in science classrooms.

The use of different types of stains in the quantification of proteins separated on gels using electrophoresis offers the capability of deriving good outcomes in terms of linear dynamic range, sensitivity, and compatibility with specific proteins. An inexpensive, simple, and versatile lighting system based on liquid crystal display backlighting is described. It is used with a flatbed scanner technique previously reported. The results from experimentation and analysis were benchmarked against a commercial densitometer to verify the performance of this analysis system. The availability of this device is expected to be useful in laboratories in schools and in resource-limited venues. (Contains 4 figures.)

The integrated absorbance areas of vibrational bands of CO[subscript 2], CO, and CH[subscript 4] gases in cigarette smoke were measured from Fourier transform infrared (FTIR) spectra to derive the partial pressures of these gases at different smoke times. The quantity of the three gas-phase components of cigarette smoke at different smoke times were then determined. The concepts and applications of the FTIR spectroscopic technique, the Beer-Lambert law, infrared band strengths, emission rates of gases, ideal gas law, and experimental hazards were effectively demonstrated and discussed for a laboratory experiment intended for upper-division undergraduate chemistry students. (Contains 1 table and 5 figures.)

The present study contributes to the constructivist research programme (RP) into learning science by comparing patterns in responses from two groups of learners--senior high school students and pre-service teachers--in the same educational context (Singapore), to a diagnostic instrument relating to the topic of ionisation energies. This topic is currently included in the curriculum for 16- to 19-year-old students studying chemistry in Singapore (and elsewhere). The comparison shows that: (1) although graduate pre-service teachers offered some types of incorrect responses less frequently than high school students; (2) they retained high levels of alternative conceptions commonly found among high school students; and (3) of particular note, certain alternative conceptions were found to be "more" common among the graduates. This suggests the intuitive appeal of certain alternative conceptions is such that they can readily be reproduced down "generations" of learners. The findings are explored in terms of a range of conceptual resources that have been developed within the constructivist RP. The analysis suggests that the curriculum sets out inappropriate target knowledge for senior high school students, given the nature of the subject matter and the prior learning of the students. It is also suggested that it may be fruitful to consider conceptual learning in terms analogous to the RP found in science, and that from this perspective certain insidious alternative conceptions can be understood as derived from commitments that are taken for granted and protected from explicit challenge by a protective belt of refutable auxiliary conceptions. (Contains 4 tables and 5 figures.)

In chemical kinetics, in addition to the concepts related to kinetics, stoichiometry, chemical equilibrium and the characteristics of the reactants are often involved when comparing the rates of different reactions, making such comparisons very challenging for students at all levels, as well as for pre-service science teachers. Consequently, four multiple-choice items were developed to determine the understanding of 217 pre-service science teachers of the kinetics of acid reactions that are taught at the Grade 9 to 10 levels in Singapore schools. Each of four items compared two different acid reactions under similar conditions, and respondents were required to select the best graphical representation for the two reactions. Respondents were also required to provide reasons to explain their particular selection for each item. In addition, one item on the dissociation of sulfuric acid and two items involving excess/limiting reagents were also included to provide additional data on the pre-service teachers' understanding of these concepts that were assessed in the four items on kinetics of acid reactions. The results showed that the pre-service teachers had difficulties in explaining the properties of different common acids, including the dissociation of the acids and how these affect the rates of the different acid reactions. This study highlights the importance of determining pre-service teachers' understanding of the concepts that they will be teaching with a view to addressing areas of difficulty, as these will have consequences on their future students' learning. (Contains 4 tables and 14 figures.)

The results from a study to explore pre-service teachers' understanding of ionization energy, a topic that features in A-level (grade 11 and 12) chemistry courses. in Singapore , is described. A previous study using a two-tier multiple choice diagnostic test has shown that Singapore A-level students have considerable difficulty understanding the topic of ionization energy. The same diagnostic test was administered to a total of 237 pre-service chemistry teachers from 2003 to 2006, and it was found that the pre-service teachers had similar difficulties and alternative conceptions as the A-level students. Teachers need to be aware of their students' as well as their own alternative conceptions so that they can address their subject matter knowledge and be better able to support their students' learning of difficult topics in chemistry. (Contains 4 tables.)

This paper describes findings from a study to explore Singapore A-level (Grades 11 and 12, 16-19 yr old) students' understanding of ionisation energy, an abstract and complex topic that is featured in school chemistry courses. Previous research had reported that students in the United Kingdom commonly use alternative notions based on the perceived stability of full shells and the "sharing out" of nuclear force, but that such ideas tend to be applied inconsistently. This paper describes results from the administration of a two-tier multiple-choice instrument, the ionisation energy diagnostic instrument, to find (1) whether A-level students in Singapore have similar ways of thinking about the factors influencing ionisation energy as reported from their A-level counterparts in the UK; and (2) how Singapore A-level students explain the trend of ionisation energy across different elements in Period 3. The results indicate that students in Singapore use the same alternative ideas as those in the UK, and also a related alternative notion. The study also demonstrates considerable inconsistency in the way students responded to related items. The potential significance of the findings to student understanding of complex topics across the sciences is considered.

With the widening knowledge base students will need to be more flexible in their learning habits. Traditionally, teaching school science often involves teacher-centred methods like lectures, experimental demonstration or guided inquiry. Plain knowledge dissemination will not adequately prepare students to cope with the changing world. Hence, schools need to train students to be reflective in their learning habits--that is, getting students to be observant, to generate relevant alternatives and to make sense of these ideas. This article discusses a well-documented reflective learning strategy--the use of "what if" questions, to help students extend their learning beyond curricular requirements. Students are introduced to a distillation set up and then asked to pose "what if" questions about it. Their questions and the corresponding peer responses are a wealth of information for teachers to explore how science may be taught differently and with a greater impact on their students' learning experience. (Contains 3 tables and 2 figures.)

Chemistry teachers face constraints when trying to integrate cognitive and affective objectives, and hence thoughtful lesson planning is required to achieve the goal. Chemistry teachers can educate students to be knowledgeable about chemical concepts, processes and the benefits of responsible practice by the chemical industry, while being aware, and prepared to act against hazards posed by the chemical industry or threats of chemical terrorism.

Previous research has shown that students' existing conceptions are critical to subsequent learning because there is interaction between the new knowledge that the students encounter and their existing knowledge from previous lessons. Taber (1999a) found A-level students in the UK had difficulty in understanding the principles determining the magnitude of ionization energy because of their pre-existing octet rule framework. In a related study, Tan et al. (2005) explored the conceptions of ionization energy of A-level students in Singapore, and found that these students also applied the octet rule framework to decide if an isolated sodium ion would recombine with an electron to reform the sodium atom, and whether another electron could be removed from the sodium +1 (Na[superscript +]) ion. In addition, the study found that there appeared to be an offshoot of the octet rule framework, he "stable fully-filled and half-filled sub-shell" thinking, which the students in Singapore used to explain the trend of ionization energies across Period 3. (Contains 5 tables.)

This paper describes the analysis of two commonly used high school (Grades 11 and 12) chemistry textbooks in Singapore to determine if the content presented in the topic of intermolecular forces is consistent with the concepts and propositional knowledge identified by the authors as essential for the learning and understanding of the topic according to the Singapore high school chemistry syllabus. The authors found that the two textbooks did not adequately discuss the electrostatic nature of intermolecular forces, and the factors influencing the polarity of bonds/molecules, hydrogen bonding and instantaneous dipole-induced dipole interactions. The insufficient coverage of the above areas may lead to students having alternative conceptions of intermolecular forces as they may have incomplete or little understanding of the concepts involved and relationships between these concepts. Thus, teachers need to analyse textbooks carefully before using the textbooks so that they can be more aware of the difficulties that students may face when reading the textbooks, and attend to these areas by careful elaboration and integration of concepts in their lessons.

Uses a two-tier, multiple-choice diagnostic instrument to determine (n=915) grade 10 students' understanding of the acid, base, and salt reactions involved in basic qualitative analysis. Reports that many students did not understand the formation of precipitates and the complex salts, acid/salt-base reactions, and thermal decomposition involved in qualitative analysis. (Contains 16 references.) (Author/YDS)

This study investigated the effects of incorporating concept mapping into computer assisted instruction with tenth grade students in Singapore. Discusses results of a chemistry achievement test that suggest that concept mapping accompanying a computer assisted tutorial program can enhance their learning, and considers future research. (Contains 30 references.) (Author/LRW)

Discussion of technological innovation and the process of design focuses on the design of computer software. Offers a framework for understanding the design process by examining two computer programs: FliPS, a multimedia program for learning complex problems in chemistry; and Tiger, a Web-based program for managing and publishing electronic manuscripts. (Author/LRW)

Outlines problems students have with understanding the abstract concept of chemical bonding as revealed in previous research. Describes the development of a two-tier multiple-choice diagnostic instrument for assessing alternative conceptions about chemical bonding held by 14-16 year olds. Discusses the instrument and its findings for a group of Australian students (n=119). (Contains 18 references.) (Author/WRM)

In this work, we report the thermal kinetics, thermodynamics, and decomposition mechanism of AP-based molecular perovskite energetic materials and estimate their thermal safety performance. Typical AP-based molecular perovskite energetic materials, ([H.sub.2]dabco)[N[H.sub.4][(Cl[O.sub.4]).sub.3]] (DAP-4), ([H.sub.2]pz)[N[H.sub.4][(Cl[O.sub.4]).sub.3]](PAP-4), ([H.sub.2]mpz)[N[H.sub.4][(Cl[O.sub.4]).sub.3]](PAP-M4), and ([H.sub.2]hpz)[N[H.sub.4][(Cl[O.sub.4]).sub.3]] (PAP-[H.sub.4]), were synthesized and characterized. These were studied using differential scanning calorimetry (DSC). The results show that all of the obtained AP-based molecular perovskite energetic materials have higher thermal decomposition temperatures, and the peak temperatures are more than 360 [degrees]C. All follow random nucleation and growth models. Other thermodynamic parameters, such as the reaction enthalpy ([DELTA]H), entropy change ([DELTA]S), and Gibbs free energy ([DELTA]G), show that they are generally thermodynamically stable. Moreover, their adiabatic induced temperatures were obtained; [T.sub.D24] of DAP-4, PAP-4, PAP-M4, and PAP-[H.sub.4] were 246.6, 201.2, 194.5, and 217.5 [degrees]C, respectively. This study offers an important and in-depth understanding of the thermal decomposition characteristics of AP-based molecular perovskite energetic materials and their potential applications. Key words: AP-based molecular perovskite energetic materials, DAP-4, thermal kinetics, thermal safety performance. Dans le cadre des présents travaux, nous avons étudié la cinétique thermique, la thermodynamique et le mécanisme de décomposition des matériaux énergétiques de type pérovskite moléculaire à base de perchlorate d'ammonium (PA), et nous avons évalué leurs performances en matière de sécurité thermique. Nous avons synthétisé et caractérisé des matériaux énergétiques représentatifs de type pérovskite moléculaire à base de PA ([H.sub.2]dabco)[N[H.sub.4][(Cl[O.sub.4]).sub.3]] (DAP-4), ([H.sub.2]pz) [N[H.sub.4][(Cl[O.sub.4]).sub.3]] (PAP-4), ([H.sub.2]mpz)[N[H.sub.4][(Cl[O.sub.4]).sub.3]] (PAP-M4) et ([H.sub.2]hpz)[N[H.sub.4][(Cl[O.sub.4]).sub.3]] (PAP-[H.sub.4]). Nous les avons également étudiés par calorimétrie différentielle à balayage (DSC, differential scanning calorimetry). Les résultats montrent que tous les matériaux énergétiques type pérovskite moléculaire à base de PA présentent des températures de décomposition thermique plus élevées, et que les températures de pointe sont supérieures à 360 [degrees]C. En outre, tous suivent le modèle de nucléation et de croissance aléatoires. D'autres paramètres thermodynamiques, tels que l'enthalpie de réaction ([DELTA]H), la variation d'entropie ([DELTA]S) et l'énergie libre de Gibbs ([DELTA]G), montrent qu'ils sont généralement stables sur le plan thermodynamique. De plus, nous avons obtenu les températures d'induction adiabatiques; le [T.sub.D24] du DAP-4, du PAP-4, du PAP-M4 et du PAP-[H.sub.4] étant respectivement de 246,6, de 201,2, de 194,5 et de 217,5 [degrees]C. Ces travaux permettent d'approfondir de manière importante la compréhension des caractéristiques de décomposition thermique des matériaux énergétiques de type pérovskite moléculaire à base de PA et de leurs applications potentielles. [Traduit par la Rédaction] Mots-clés : matériaux énergétiques de type pérovskite moléculaire à base de perchlorate d'ammonium, DAP-4, cinétique thermique, performances de sécurité thermique., 1. Introduction In recent years, with the increase in the functional requirements of energetic materials in civilian and military applications, energetic materials with unique and excellent characteristics have attracted widespread [...]