Chemistry Education

Project-based learning (PBL), which is increasingly supported by information technologies (IT), contributes to fostering student-directed scientific inquiry of problems in a real-world setting. This study investigated the integration of PBL in an IT environment into three undergraduate chemistry courses, each including both experimental and control students. Students in the experimental group volunteered to carry out an individual IT-based project, whereas the control students solved only traditional problems. The project included constructing computerized molecular models, seeking information on scientific phenomena, and inquiring about chemistry theories. The effect of the PBL was examined both quantitatively and qualitatively. The quantitative analysis was based on a pretest, a posttest, and a final examination, which served for comparing the learning gains of the two research groups. For the qualitative analysis, we looked into the experimental students' performance, as reflected by the projects they had submitted. In addition, “think alou” interviews and observations helped us gain insight into the students' conceptual understanding of molecular structures. Students who participated in the IT-enhanced PBL performed significantly better than their control classmates not only on their posttest but also on their course final examination. Analyzing the qualitative findings, we concluded that the construction of computerized models and Web-based inquiry activities helped promote students' ability of mentally traversing the four levels of chemistry understanding: symbolic, macroscopic, microscopic, and process. More generally, our results indicated that incorporating IT-rich PBL into freshmen courses can enhance students' understanding of chemical concepts, theories, and molecular structures. © 2004 Wiley Periodicals, Inc. Sci Ed89:117–139, 2005

BeH is one of the most important benchmark systems for ab initio methods and for studying Born-Oppenheimer breakdown. However the best empirical potential and best ab initio potential for the ground electronic state to date give drastically different predictions in the long-range region beyond which measurements have been made, which is about ~1000 cm-1 for 9BeH, ~ 3000 cm-1 for 9BeD, and ~ 13000 cm-1 for 9BeT. Improved empirical potentials and Born-Oppenheimer breakdown corrections have now been built for the ground electronic states X(1^2 Sigma^+) of all three isotopologues. The predicted dissociation energy for 9BeH from the new empirical potential is now closer to the current best ab initio prediction by more than 66% of the discrepancy between the latter and the previous best empirical potential. The previous best empirical potential predicted the existence of unobserved vibrational levels for all three isotopologues, and the current best ab initio study also predicted the existence of all of these levels, and four more. The present empirical potential agrees with the ab initio prediction of all of these extra levels not predicted by the earlier empirical potential. With one exception, all energy spacings between vibrational energy levels for which measurements have been made, are predicted with an agreement of better than 1 cm^{-1} between the new empirical potential and the current best ab initio potential, but some predictions for unobserved levels are still in great disagreement, and the equilibrium bond lengths are different by orders of magnitude.

This study investigated the attainment of chemical literacy among 10 th -12 th grade chemistry students in Israel. Based on existing theoretical frameworks, assessment tools were developed, which measured students' ability to: a) recognize chemical concepts as such (nominal literacy); b) define some key-concepts (functional literacy); c) use their understanding of chemical concepts to explain phenomena (conceptual literacy); and d) use their knowledge in chemistry to read a short article, or analyze information provided in commercial ads or internet resources (multi-dimensional literacy). It was found that students improve their nominal and functional literacy; however, higher levels of chemical literacy, as defined within these frameworks, are only partly met. The findings can be helpful in the process of designing new curricula, and emphasizing certain instructional strategies in order to foster chemical literacy. [Chem. Educ. Res. Pract., 2006, 7 (4), 203-225]

The purpose of this study was to investigate the effects on students' achievement and misconceptions of new teaching material developed for the unit 'acids and bases'. Also, the students' attitudes towards chemistry were explored. The new material included worksheets based on the conceptual conflict strategy. The sample consisted of eighty-eight students. The research was carried out with an experimental/control group design, and lasted for four weeks. Two instruments 'The Concept Achievement Test' and 'Chemistry Attitude Scale' were used to collect data before and after the study as pre-tests and post-tests. The results from the post-tests indicated that the students in the experimental group, taught with the new teaching material, showed significantly greater achievement in the unit than did the students in the control group. In addition, the experimental group had a significantly higher score than the control group with regard to their attitudes toward chemistry. This shows that the implementation of the new material produced better results both in terms of achievement and attitudes. The students' misconceptions in experimental group were less than the control group. [Chem. Educ. Res. Pract., 2005, 6 (1), [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51]

In a preceding publication (Tsaparlis, G., Pappa, E. T., & Byers, B. (2018). Teaching and learning chemical bonding: Research-based evidence for misconceptions and conceptual difficulties experienced by students in upper secondary schools and the effect of an enriched text. Chemistry Education Research and Practice, 19(4), 1253-1269), we reviewed previous studies on students' misconceptions and conceptual difficulties with the topic of chemical bonding and tested the knowledge of tenth-grade Greek students on certain key aspects of bonding. In addition, we presented an enriched teaching text on this topic for the tenth grade and examined its effectiveness with regard to the same aspects of bonding. In the present study, we review earlier studies, which made proposals concerning the teaching of this topic, and provide some proposals of our own, based on the findings of our previous study. We recommend that a spiral curriculum spanning all three upper-secondary grades should be adopted. A learning progressions approach, employing lower and upper anchors of relevant scientific knowledge is considered, and a proposed list of potential core concepts, lever concepts, and stepping-stones are presented. Finally, the pros and cons of a modern qualitative quantum mechanical approach to bonding are considered.

https://orcid.org/0000-0002-0856-747X

This article studies two kinds of information extracted from statistical correlations between methods for assigning net atomic charges (NACs) in molecules. First, relative charge transfer magnitudes are quantified by performing instant least squares fitting (ILSF) on the NACs reported by Cho et al. (ChemPhysChem, 2020, 21, 688-696) across 26 methods applied to $2000 molecules. The Hirshfeld and Voronoi deformation density (VDD) methods had the smallest charge transfer magnitudes, while the quantum theory of atoms in molecules (QTAIM) method had the largest charge transfer magnitude. Methods optimized to reproduce the molecular dipole moment (e.g., ACP, ADCH, CM5) have smaller charge transfer magnitudes than methods optimized to reproduce the molecular electrostatic potential (e.g., CHELPG, HLY, MK, RESP). Several methods had charge transfer magnitudes even larger than the electrostatic potential fitting group. Second, confluence between different charge assignment methods is quantified to identify which charge assignment method produces the best NAC values for predicting via linear correlations the results of 20 charge assignment methods having a complete basis set limit across the dataset of $2000 molecules. The DDEC6 NACs were the best such predictor of the entire dataset. Seven confluence principles are introduced explaining why confluent quantitative descriptors offer predictive advantages for modeling a broad range of physical properties and target applications. These confluence principles can be applied in various fields of scientific inquiry. A theory is derived showing confluence is better revealed by standardized statistical analysis (e.g., principal components analysis of the correlation matrix and standardized reversible linear regression) than by unstandardized statistical analysis. These confluence principles were used together with other key principles and the scientific method to make assigning atom-in-material properties non-arbitrary. The N@C 60 system provides an unambiguous and non-arbitrary falsifiable test of atomic population analysis methods. The HLY, ISA, MK, and RESP methods failed for this material.

This study sought to determine the levels of conceptual understanding of undergraduate students regarding organic compounds within different functional groups. A total of 60 students who were enrolled in the Department of Secondary Science and Mathematics Education of a Faculty of Education
at a state university in Turkey and who had followed an Organic Chemistry Laboratory Course participated in the study. The data were collected using two tools: functional group worksheets and concept maps. Both qualitative and quantitative evaluations were used in analyzing the data. The
findings showed that the students generally had low levels of understanding of concepts relating to functional groups, and they exhibited a considerable number of misconceptions. Considering the findings more fully, it was determined that students have remarkable misconceptions and low levels of
understanding about certain topics regarding functional groups, including the physical properties of functional groups, intermolecular bonds, acidity and basicity, reduction and oxidation, stereoisomerism and structural isomerism, and aromaticity and aliphaticity, as well as other organic chemistry concepts (e.g. decarboxylation, oxyacide, and phenol). The results suggest that since students are unable to adequately comprehend the subjects of general chemistry, such as intramolecular and intermolecular bonds, acidity and basicity, oxidation and reduction and determination of molecular structures, they fail to accurately transfer their knowledge to learning about organic chemistry. In order to promote
students’ understanding of functional groups and prevent related misconceptions, it is recommended that basic chemistry topics should be reinforced, and the relationship between students’ current knowledge and the new information to be learned in organic chemistry should be emphasized with the help of activities in which various forms of thinking are used.

Current views on metacognition consider it a fundamental factor in learning and problem‐solving which in turn has led to interest in creating learning experiences conducive to developing its use. This paper reports on the effectiveness of a collaborative intervention in promoting college general chemistry students’ awareness and use of metacognition. The intervention starts with a cognitive imbalance experience as a trigger for metacognitive reflection, which is then followed by reflective prompting and peer interaction. A quasi‐experimental control and treatment design with 537 and 464 participants, respectively, was implemented. Assessment of metacognition was accomplished by using a multi‐method instrument that consists of a self‐report (Metacognitive Activities Inventory, MCAI) and a concurrent, web‐based tool (Interactive Multimedia Exercises, IMMEX). IMMEX has been shown to allow rapid classification of problem solvers according to their regulatory metacognitive skills. Compared to the control group, the treatment group showed a significant increase in metacognition awareness, as evidenced by the MCAI, increased ability in solving non‐algorithmic chemistry problems of higher difficulty, and with a higher per cent correctness (IMMEX). These findings are consistent with an overall increase in the use of regulatory metacognitive skills by the treatment group. We propose that the meaningful, purposeful social interaction and the reflective prompting instantiated by the intervention act as promoters of metacognition development. It is of particular relevance that these factors are not exclusive to the intervention employed here and can be embedded by practitioners in their instruction.

The current research on systems thinking criticizes the additive nature of green chemistry
(GC) not being supportive of systems thinking to achieve holism in its practices. This paper argues
that systems thinking should comprise of the social issues, and, therefore, it studies renowned
papers by GC pioneers and reviews on the field regarding how they address the social dimension
of sustainability. It points out how GC has ignored social sustainability in its discourses, practices,
and evaluations, leading to a reductionist interpretation of sustainability. Then, this paper presents
some challenges to be overcome in order to achieve balanced sustainability. A systemic chemical
thinking is advocated, considering chemistry in culture and chemistry as culture, expanding the
chemistry rationality from ontological and technological dimensions into the epistemological and
ethical ones. It is then discussed how chemistry education can help to promote sustainability in
a broad and systemic way.

The aim of this research was to examine the chemical representations that are present in Turkish high school chemistry textbooks. Content analysis was the method of analysis. Four chemistry textbooks, which were commonly used in Turkey, for each grade (i.e., from 9th to 12th), were selected. When evaluating the representations, a rubric including five main criteria was used: (1) type of representation, (2) interpretation of representations’ surface features, (3) representations’ relatedness to text, (4) properties of representations’ caption, and (5) degree of correlation between subordinates comprising a multiple representation. The results of the research revealed that the chemical representations used in the textbooks are mainly macroscopic, symbolic, and hybrid. Majority of the representations had explicit surface features and appropriate captions. Moreover, they were completely related to the text. Most of the multiple representations had sufficient links between their subordinates. Recommendations for textbook writers and future research are provided

Identifying students' misconceptions and learning difficulties and finding effective ways of addressing them has been one of the major concerns in chemistry education. However, the chemistry education community has paid little attention to determining discipline-specific aspects of chemistry that can lead to learning difficulties and misconceptions. In this article, it is argued that emergence plays a critical role in the epistemology and the ontology of chemistry and hence it should be taken into account for understanding learning difficulties and finding ways of addressing them in chemistry. It is particularly argued that one of the fundamental sources of learning difficulties and chemical misconceptions is learners' failure to understand the emergent nature of chemical entities, their properties, and interactions. In this article, an interpretive analysis framework is suggested for identifying specific learning demands and the sources of learners' misconceptions about the emergent chemical properties and phenomena. Findings from previous research on learners' misconceptions regarding emergent chemical properties are reanalyzed and interpreted through this framework. Inadequacies of typical teaching practices and their consequences are discussed from an emergentist perspective. Finally, implications of the emergentist perspective for more meaningful chemical education are discussed.

A PBL laboratory-based module for first year undergraduate chemistry has been developed and successfully implemented. Its aim was to develop the students' practical and transferable skills, as well as their content knowledge and scientific understanding, and also to address the concern expressed in the literature over the effectiveness of the traditional laboratory courses to achieve these aims. The PBL module also encouraged students to prepare for their laboratory session in an active and collaborative manner through pre-lab exercises. By combining elements of group work, discussion, hands-on activities and alternative assessment methods, the students were provided with an environment conducive to meaningful, deep learning. We describe how the PBL module was developed by adapting the experience for the students rather than changing the experiments. Specific examples from analytical, physical and organic chemistry are given with a focus on the pre-laboratory exercises, associated group work, and the assessment methods, as well as on the actual practical work. [Chem.

Bond order quantifies the number of electrons dressed-exchanged between two atoms in a material and is important for understanding many chemical properties. Diatomic molecules are the smallest molecules possessing chemical bonds and play key roles in atmospheric chemistry, biochemistry, lab chemistry, and chemical manufacturing. Here we quantum-mechanically calculate bond orders for 288 diatomic molecules and ions. For homodiatomics, we show bond orders correlate to bond energies for elements within the same chemical group. We quantify and discuss how semicore electrons weaken bond orders for elements having diffuse semicore electrons. Lots of chemistry is effected by this. We introduce a first-principles method to represent orbital-independent bond order as a sum of orbital-dependent bond order components. This bond order component analysis (BOCA) applies to any spin-orbitals that are unitary transformations of the natural spin-orbitals, with or without periodic boundary conditions, and to non-magnetic and (collinear or non-collinear) magnetic materials. We use this BOCA to study all period 2 homodiatomics plus Mo 2 , Cr 2 , ClO, ClO À , and Mo 2 (acetate) 4. Using Manz's bond order equation with DDEC6 partitioning, the Mo-Mo bond order was 4.12 in Mo 2 and 1.46 in Mo 2 (acetate) 4 with a sum of bond orders for each Mo atom of $4. Our study informs both chemistry research and education. As a learning aid, we introduce an analogy between bond orders in materials and message transmission in computer networks. We also introduce the first working quantitative heuristic model for all period 2 homodiatomic bond orders. This heuristic model incorporates s-p mixing to give heuristic bond orders of 3 4 (Be 2), 1 3 4 (B 2), 2 3 4 (C 2), and whole number bond orders for the remaining period 2 homodiatomics.

The purpose of this study was to develop a valid and reliable scale measuring the Indonesians’ scientific habits of mind (SHOM) levels via the SSIs in context. The sample of the study consisted of 658 Indonesian people (aged 18–68 years; 385 females and 273 males; mean age: 35.5) randomly drawn from 3 districts of Special Region of Yogyakarta, Indonesia. To ensure content validity, the researchers matched SHOM (mistrust of arguments from authority, open-mindedness, scepticism, rationality, objectivity, suspension of belief, and curiosity) with the SSIs in the Indonesian context. A group of experts and a pilot study with 10 lay people ensured face validity. Concurrent validity was verified via independent samples t-test. To confirm convergent and discriminant validity, confirmatory factor analysis, and reliability values were calculated. Because the final version (33 items) of the SHOM scale has high validity in content, face, convergent, discriminant, and concurrent, it provides valid conclusions based on the theoretical constructs for the sub-scales. This suggests that the SHOM scale may be adapted or improved for SSIs in different contexts.

Addressing the contemporary waste management is seeing a shift towards energy production while managing waste sustainably. Consequently, waste treatment through gasification is slowly taking over the waste incineration with multiple benefits, including simultaneous waste management and energy production while reducing landfill volumes and displacing conventional fossil fuels. Only in the UK, there are around 14 commercial plants built to operate on gasification technology. These include fixed bed and fluidized bed gasification reactors. Ultra-clean tar free gasification of waste is now the best available technique and has experienced a significant shift from two-stage gasification and combustion towards a one-stage system for gasification and syngas cleaning. Nowadays in gasification sector, more companies are developing commercial plants with tar cracking and syngas cleaning. Moreover, gasification can be a practical scheme when applying ultra-clean syngas for a gas turbine with heat recovery by steam cycle for district heating and cooling (DHC) systems. This chapter aims to examine the recent trends in gasification-based waste-to-energy technologies. Furthermore, types of gasification technologies, their challenges and future perspectives in various applications are highlighted in detail.

Although chemistry-focused socio-scientific issues support the ‘relevance’ model of chemistry education, the related literature has lacked any systematic review handling them together. For this reason, this research aimed to thematically synthesize the research papers on chemistry-focused socio scientific issues (SSI) from 2008 to 2020 and inferentially evaluate them in terms of the relevance model of chemistry education. After searching international and national well-known databases through relevant keyword patterns (e.g., Pattern 1: socio-scientific issues and chemistry education), 65 research papers were apparent for the systematic review. Then, the authors generated primary and secondary codes for the research papers and then inferentially marked their ‘relevance’ components. The systematic review indicated variation of research areas (e.g., relevance model of chemistry education) and dominant research foci for different themes (e.g., competencies and related variables for the theme ‘aims’; pollution, energy, industry and fabrication-based problems for the theme ‘SSI’; organic compounds for the theme ‘chemistry concepts’). Further, it revealed that the research papers on chemistry-focused SSI had some shortcomings at handling all components of the relevance model in a balanced way. The current research suggests professionally training teachers about how to integrate chemistry-focused SSI and the relevance model into school chemistry.

Educational transformation in the 21st century demands in-depth knowledge and understanding in order to promote the development of higher-order thinking skills (HOTS). However, the most commonly reported problem with respect to developing a knowledge of chemistry is poor mastery of basic concepts. Chemistry laboratory educational activities are shown to be less effective in developing an optimum conceptual understanding and HOTS among students. One factor is a lack of effective assessment and evaluation tools. Therefore, the primary focus of this study is to explore concept maps as an assessment tool in order to move students' thinking skills to a higher level during laboratory learning activities. An embedded mixed method design is used in this study, which has also employed a pre-experimental research design. This design triangulates quantitative and qualitative data, which are combined to strengthen the findings. A low-directed concept mapping technique, convergence scoring method, and pre-post laboratory concept map were used in this study. An electrolysis HOTS test was used as the research instrument in order to measure the level of student achievement with respect to high-level questions. In addition, the thought process that is involved when students construct concept maps has been explored and studied in detail by utilising a think-aloud protocol. Results showed a positive development towards understanding and higher level thinking skills in students with respect to electrolysis concepts learned through chemistry laboratory activities. An investigation of the students' thinking processes showed that high-achieving students were more capable of giving a content-based explanation of electrolysis and engaged in monitoring activities more often while building a concept map. Nonetheless, all categories of students managed to show a positive increase in the activities of explanation and monitoring during the construction of concept maps after they were exposed to the assessment tool in the laboratory learning activities. In conclusion, the assessment activity using concept maps in laboratory learning activities has a positive impact on students' understanding and stimulates students to increase their HOTS.

Consensus does not exist among chemists as to the essential characteristics of inquiry in the undergraduate laboratory. A rubric developed for elementary and secondary science classrooms to distinguish among levels of inquiry was modified for the undergraduate chemistry laboratory. Both peer-reviewed experiments in the literature and commercially available experiments were evaluated using the rubric, revealing a diversity of uses for the word inquiry. The modified rubric provides a valid and reliable standard of measure for chemists to examine their laboratory curriculum. [Chem. Educ. Res. Pract., 2007, 8 (2), 212-219.]

Transesterification of camelina oil using supercritical methanol with hexane as a cosolvent and subcritical methanol along with potassium hydroxide as a cosolvent/catalyst was investigated to study the methyl ester conversion process. It was found that cosolvents play a vital role in reducing the severity of critical operational parameters and maximize the biodiesel yield. The experimental results from the process parametric evaluation studies show that supercritical methanol with hexane as a cosolvent could produce maximum methyl esters using the following conditions: reaction temperature of 290°C, methanol to oil ratio of 45, and reaction time of 40 min. For subcritical methanol condition with 0.3 wt % potassium hydroxide as a cosolvent, methyl ester yields of þ90% are obtained using the following conditions: reaction temperature of 180°C, methanol to oil molar ratio of 30, and a reaction time of 20 min. Process variables critical to the methyl ester conversion are determined to be cosolvent ratio, molar ratio of alcohol to oil, and reaction time. Fuel properties of the biodiesel produced are comparable to those of regular diesel and conform to the ASTM standards.

Research in chemistry education has highlighted a number of variables that predict learning and performance, such as teacher–student interactions, academic motivation and metacognition. Most of this chemistry research has examined these variables by identifying dyadic relationships through bivariate correlations. The main purpose of this study was to simultaneously investigate students' perceptions of teacher–student interactions (autonomy support), motivation (expectancy, importance, utility and interest), metacognitive strategies for problem solving (planning, monitoring and evaluation), and performance in chemistry. Measures were collected from 503 Spanish undergraduates (53.13% females) aged 18 to 36 years. Structural equation modeling (SEM) tested the hypothesized direct and mediated relations between these variables. First, confirmatory factor analysis (CFA) provided evidence of the robustness of the evaluation instruments. Second, perceived autonomy support positively pre...

(A Teaching/Learning Sequence on Substance and Chemical Reaction Concepts, Based on Nature of Science and Technology)
Inside the international research project Teaching and Learning about Nature of Science and Technology: An experimental and longitudinal research (EANCYT, acronym in Spanish), a teaching/learning sequence is described, which has been designed to improve the comprehension of the Nature Of Science (NoS) and Technology, trying to help students of the General Chemistry course in Undergraduate Education to learn adequate ideas around the scientific compe-tences of «defining» and «modeling». This sequence involves students in an inquiry process related with the history and the definitions of the concepts «substance» and «chemical reaction», two of greatest importance in any chemistry course. Throughout the sequence, students will gradually improve the definitions of these two concepts from the macroscopic level to the nanoscopic one, trying them to be convinced that “defining is modeling”. The students will face the reading of essays on historical and experimental facets of both concepts. Additionally, it is analyzed here the carrying out of the sequence with a group of students on the first semes¬ter of 2012, and the changes that were done after this evaluation.
Keywords: Nature of Science (NoS), teaching/learning sequence, substance, chemical reaction, defining, modeling

Promoting students’ attitudes, a part of affective domains is a major goal in higher education. Unfortunately, only a few studies were available related to the improvement of pre-service chemistry teachers’ attitudes as this domain was rarely explored using a mixed teaching approach. In this quasi-experimental research, we investigated the effect of the Research-Oriented Collaborative Inquiry Learning (REORCILEA) in improving students’ scientific attitudes. A total of sixty-four (6 males, 58 females) first-year pre-service chemistry teachers at the Department of Chemistry Education of a public university in Indonesia attended the General Chemistry course. In order to collect the data, the Scientific Attitudes Scale and Interview Protocol were administered. The data were then analyzed using t-test and thematic analysis. The results of the t-test revealed that students in the experimental group obtained significantly greater scores than the ones of the control group regarding their scientific attitudes. After analyzing the interview data qualitatively, students who were exposed to non-traditional teaching approach had stronger learning interests and enjoyed the chemistry lectures. In conclusion, REORCILEA model could be considered more effective in improving students’ scientific attitudes compared to conventional teaching methods

Abstract: The field of nanotechnology is the most active area of research in modern materials science. Though there are many chemical as well as physical methods, green synthesis of nanomaterials is the most emerging method of synthesis. We report the synthesis of antibacterial Silver nanoparticles (AgNPs) using flower of medicinal herb, Aerva lanata. The synthesized AgNPs have been characterized by UV-Vis spectroscopy, FT-IR, transmission electron microscopy (TEM) and Cyclic Voltammetry(CV). The mean particle of synthesized NPs was found to be 43.5 nm, as confirmed by TEM. FTIR analysis revealed that the AgNPs were stabilized by proteins, polyphenols and other aromatic compounds present in the extract. Such AgNPs stabilized by Aerva lanata flower extract were found to have enhanced antimicrobial activity against well-known pathogenic strains, namely E.Coli, Staphylococus aureus, Bascillus cereus and Pseudomonas aeruginosa. Keywords: Silver Nanoparticles; Aerva lanata; TEM; Antibacterial activity;

The COVID-19 pandemic has placed pressure on institutions, and especially instructors, to deliver course content in innovative ways, often with limited resources. In face-to-face learning, many chemistry instructors value inquiry-based learning with real-world applications. These types of learning activities cultivate student interest and, thus, motivate students to achieve their best. However, inquiry-based learning can be more challenging in an online environment, especially given limited resources and preparation time. This paper describes an inquiry-based laboratory demonstration that is inexpensive and easy to conduct outside of the traditional laboratory setting and yet provides a valuable learning experience for second-semester organic chemistry students. In this activity, students apply their knowledge of chemistry to the proteins, carbohydrates, and lipids in bovine milk, studying the casein protein, lactose, fatty acids, and more. Students complete a pre-lab assignment individually, watch prerecorded demonstrations via the Zoom video-conferencing platform, and complete a guided inquiry worksheet in groups, via breakout rooms. These activities help students review concepts such as solubility, hydrogen bonding, and acidity and invite them to apply new material on carbonyl chemistry, hydrolysis, and the relationship between protein structure and function. Because this learning activity challenges students to explore real-world implications, it deepens their understanding of the intricate interplay between organic chemistry, biochemistry, and microbiology and thus prepares them for further scientific inquiry in these areas.

Students commencing studies in biochemistry must transfer and build on concepts they learned in chemistry and biology classes. It is well established, however, that students have difficulties in transferring critical concepts from general chemistry courses; one key concept is “energy.” Most previous work on students’ conception of energy has focused on their understanding of energy in the context of physics (including the idea of “work”) and/or their understanding of energy in classical physical and inorganic chemistry contexts (particularly Gibbs Free Energy changes, the second law of thermodynamics, and equilibrium under standard conditions within a closed system). For biochemistry, students must go beyond those basic thermodynamics concepts of work, standard energy changes, and closed systems, and instead they must consider what energy flow, use, and transformation mean in living, open, and dynamic systems.

An open-source 3-D printable laboratory sample rotator mixer is developed here in two variants that allow users to opt for the level of functionality, cost saving and associated complexity needed in their laboratories. First, a laboratory sample rotator is designed and demonstrated that can be used for tumbling as well as gentle mixing of samples in a variety of tube sizes by mixing them horizontally, vertically, or any position in between. Changing the mixing angle is fast and convenient and requires no tools. This device is battery powered and can be easily transported to operate in various locations in a lab including desktops, benches, clean hoods, chemical hoods, cold rooms, glove boxes, incubators or biological hoods. Second, an on-board Arduino-based microcontroller is incorporated that adds the functionality of a laboratory sample shaker. These devices can be customized both mechanically and functionally as the user can simply select the operation mode on the switch or alter the code to perform custom experiments. The open source laboratory sample rotator mixer can be built by non-specialists for under US$30 and adding shaking functionality can be done for under $20 more. Thus, these open source devices are technically superior to the proprietary commercial equipment available on the market while saving over 90% of the costs.

This study aimed to investigate the effects of inquiry-based laboratory activities on high school students' understanding of electrochemistry and attitudes towards chemistry and laboratory work. The participants were 62 high school students (average age 17 years) in an urban public high school in Turkey. Students were assigned to experimental (N=30) and control groups (N=32). The experimental group was taught using inquiry-based laboratory activities developed by the researchers and the control group was instructed using traditional laboratory activities. The results of the study indicated that instruction based on inquiry-based laboratory activities caused a significantly better acquisition of scientific concepts related to electrochemistry, and produced significantly higher positive attitudes towards chemistry and laboratory. In the light of the findings, it is suggested that inquiry-based laboratory activities should be developed and applied to promote students' understanding in chemistry subjects and to improve their positive attitudes.

This paper revisits the tie-dyeing process through a bioinspired and safer alternative to nucleophilic aromatic substitution (S N Ar) reactions for an introductory organic chemistry laboratory. The simple and straightforward experiment provides students with an opportunity to gain practical experience in conducting a chemical reaction in a real-world context while applying concepts of design for biodegradability and reusability. The water-soluble reactive dye that replaces the use of a conventional S N Ar substrate does not require any heavy metals, toxic substances, or mordants but utilizes a much less toxic and safer sodium carbonate to generate the cellulosate nucleophile. This reaction generates no waste, and the end-product, the tie-dyed T-shirt, is reusable and biodegradable. Through this experiment, students can see connections between chemistry and environmental health while gaining a practical insight into dyeing chemistry, making use of a systems thinking approach. This experiment serves not only to employ safer alternatives to hazardous chemicals in the undergraduate organic chemistry laboratory but also to educate students to recognize the relevance and importance of applying green chemistry wherever it is possible, emphasizing life cycle thinking and stewardship.

The main purpose of this study was to identify prospective chemistry teachers' mental models of vapor pressure. The study involved 85 students in the Chemistry Teacher Training Department of a state university in Turkey. Participants' mental models of vapor pressure were explored using a concept test that involved qualitative comparison tasks. Additionally, 18 participants were interviewed to explore the mental models that emerged more deeply. The researcher analyzed responses using the constant comparative method to document participants' mental models and associated reasoning patterns in sufficient detail to be of practical use to instructors. Initial analysis of the data revealed that participants have many misconceptions about vapor pressure, which are similar to those reported in the literature. A more detailed constant comparative analysis revealed that these misconceptions derived mainly from three faulty mental models of vapor pressure: (1) vapor pressure of a liquid depends on the total number of vapor particles; (2) once the liquid– vapor equilibrium is established, the number of vapor particles is fixed and does not change regardless of the external effects on the system; and (3) vapor pressure is exerted only onto the surface of the liquid. The results have practical implications for teaching vapor pressure and science in general. By eliciting the underlying mental models of vapor pressure, these findings provide valuable insights for effective instructional interventions to address misconceptions.

The aim of this study was to investigate the effect of concept cartoons embedded within context-based learning approach on 8th grade students' alternative conceptions of "chemical bonding". Within a nonequivalent pretest-posttest control group design, the study was conducted with 45 8th grade students. To gather data, Chemical Bonding Concept Test (CBCT) with 16 multiple choice questions and clinical interviews with 5 open-ended questions was used to probe their conceptions. Clinical interview questions were prepared in parallel with the same alternative conceptions asked in the CBCT. At the end of the study, context-based approach was found effective at remedying alternative conceptions about chemical bonding. On the other hand, although concept cartoons are found powerful tools to remedy alternative conceptions about chemical bonding, they did not show an extraordinary effect. This suggests that we may need to use more than one intervention method to effectively remedy the alternative conceptions in chemical bonding.

Chemical eponyms possess important didactic and axiological potential
that can be utilized for implementation of the principles of humanization and historicism manifested in national educational standards. This study focused on students’ knowledge and views of eponyms in the light of history of science. 22 general chemistry students of Belarusian State University, 131 students of general and 119 students of organic chemistry of University of Oregon, all different majors, were surveyed on their knowledge and views of eponyms using a 24-item online questionnaire. Mann-Whitney coefficients were calculated to establish significant differences and Pearson chi-square test was applied to find correlations. It was found that students’ knowledge and views of eponyms are defined mostly by major: students majoring in teaching chemistry showed higher knowledge and expressed more positive views of eponyms than those majoring in non-teaching, non-chemistry and especially non-science. Other factors include students’ learning experience and study intensiveness. While didactic potential of eponyms is utilized anyway, utilization of their axiological potential depends on instructor’s willingness and mastery and should not be exaggerated as vehicles for the principles of humanization and historicism.

This study consists of a longitudinal research using an active methodology to teach the contents of the periodic table to high school students, based on project-based learning and WebQuest. The aim of this investigation is to study the relationship between learning the periodic table and the type of strategy that students choose to achieve the learning outcomes related to it. Throughout the learning process of the periodic table's chemical elements we could see that, after giving total freedom to 260 students (during 5 years of investigation) in the construction of instructional materials which helped them learn the periodic table, 195 of them chose to develop a game as a tool. There was no significant difference between genders, showing that students prefer to learn in a playful, motivating and exciting way since they felt a greater interest and had a better evaluation of what they had learned about, reaching a deeper and lasting understanding, hence, a significant learning. Gamification and learning-based games are acquiring a relevant role in education centers and teachers who apply these methodologies in pedagogical approaches have increased.

This study focused on determining the elements of mental models of atomic structure and views on visual representations of models of atomic structure in two sub-cohorts of student teachers studying at a university in Turkey. In total, 141 student teachers participated in this study. In the first cohort, the focus was on 73 freshman science student teachers' drawings of mental models of atomic structure. The analysis showed a wide variety of individual aspects in the students' minds when asked to sketch the structure of atoms. The majority of students preferred to draw two-dimensional structures, neglecting the atom's space-filling character. Concerning the details of atomic structure, the majority of students emphasized only the most essential components of atoms, namely protons, neutrons, and electrons. It was quickly recognizable that these elements were arranged according to different analogies or representations of historical models, particularly related to Bohr's atomic theory and different representations thereof. Overall, the different visual representations of atomic models the students see in school, almost exclusively serve as the basis for their ideas about atomic structure. Current atomic theory, like quantum mechanical models, are generally not used when students are asked for a "contemporary" model of atoms. Rather it seems that concreteness and functionality are the primary factors leading to the selection of an atomic model when requested. This study is supplemented by data collected from the second cohort of 68 prospective teachers consisting of a diverse group of students ranging from freshman to senior level. The students in this cohort were asked for their preferred illustrations of atoms in textbooks. Open-ended questions about atoms led to further insights. The analysis of the prospective teachers' drawings indicated that a more careful approach to teaching is necessary to clarify the relationships between different models of atomic structure and to allow students to understand what an appropriate and contemporary understanding of atomic structure should encompass.

This research follows the previ-ous study examining the effect of chemistry education on students’ perception and understanding to the nature of chemistry (NoC) as well as their attitudes towards it as a school subject. Grade 9 students (N = 282) at the end of their compulsory schooling were given a set of open-ended questions focused on their understanding to NoC, perception of chemistry topics’ importance, topics the students found interesting and their evaluation of chemistry as a school subject. The answers were analysed using the open coding approach. It is possible to conclude most of the students do not have a clear idea about the nature of chemistry. Students assess chemistry as a school subject in the middle of the 5 point Likert scale. The results of this research offer the background for a more complex analysis of effects influencing students’s conception of chemistry and its subject matter.

Conventional energy sources are limited and non-renewable and their consumption contributes to greenhouse gas emissions. The world is in
need of advanced biorefineries to meet ever growing energy demands associated with population growth and economic development. An advanced
biorefinery should use renewable and sustainable (both in quality and quantity) feedstock that gives rise to higher energy gains with minimum
non-renewable energy and resource consumption. Development of advanced biorefineries is currently encircled by two major issues. The first issue
is to ensure adequate biofuel feedstock supplies while the second issue is to develop resource-efficient technologies for the feedstock conversion
to maximize energy and economic and environmental benefits. While microalgae, microbial derived oils, and agricultural biomass and other energy
crops show great potential for meeting current energy demands in a sustainable manner, process intensification and associated synergism can
improve the resource utilization efficiency. Synergism of process intensification tools is important to increase energy efficiency, reduce chemical
utilization and associated environmental impacts, and finally process economics. Among the many process intensification methods, this commentary
provides a perspective on the essential role of MWs and US and their synergy in biofuel production. Individual, sequential, and simultaneous
applications of MWs and US irradiations can be utilized for process intensification of various biofuels production and selective recovery of high
value bioproducts. Process related barriers, namely mass and heat transfer limitations, can be eliminated by this synergism while improving the
reaction efficiency and overall process economics significantly. In this article, a brief review focused on recent developments in MW and US
mediated process intensification for biofuel synthesis and associated issues in their synergism followed by a discussion on current challenges and
future prospective is presented.

The aim of this study is to investigate the effects of some variables (gender and year of study) on science student teachers' (SSTs) chemistry attitudes. An adapted version of Chemistry Attitudes and Experiences Questionnaire was administered to 983 SSTs drawn from four different universities in the region of Eastern Black Sea, Turkey. Significant differences between genders' mean scores of the CAEQ indicate that the females somewhat develop stronger positive attitudes towards chemistry than do the males. Furthermore, because the first year of the study generally had the highest mean scores of the three subscales of the CAEQ, it can be deduced that tertiary education lacks improving the SSTs' positive chemistry attitudes to a satisfied level and/or a large effect size. Hence, its attitudinal quality should be intimately inquired.

Multi-channel, multi-neuron recording procedures were used to monitor simultaneously the spike train activity of single neurons (n = 7-16 cells/animal) in the dorsal raphe (DR) nucleus of the awake, freely moving rat. Putative serotonergic and non-serotonergic neurons were distinguished from one another on the basis of established criteria, i.e. waveform shape and duration, firing pattern and firing frequency. As a group, presumed serotonergic neurons exhibited low tonic discharge rates, depressed firing after serotonin (5HT)-1a agonist administration, and, except for the transition from sleep to waking, a general insensitivity to specific sensory or motor events. By contrast, non-serotonergic cells in midline and lateral wing sub-regions of the nucleus displayed responses to a variety of sensorimotor events including locomotion, grooming, head movement, chewing, auditory stimuli, and whisker movement (both passive and active). However, within this latter group, the sensorimotor response repertoire of individual cells was not uniform. Likewise, non-5HT cells with diverse response profiles were identified in both medial and lateral sub-regions of the nucleus. Cells categorized as non-serotonergic also had varied responses to 5HT1a agonist administration. These results emphasize the diverse input/output relationships of individual DR neurons and underscore the need for a more comprehensive analysis of such properties under waking conditions in order to obtain a better understanding of the role of the DR nucleus in brain function. D

There is a widespread concern that relatively few students, especially those from disadvantaged backgrounds, continue to study chemistry and other science subjects after compulsory education. Yet it remains unclear how different aspects of students’ background and home context, their own attitudes and beliefs, and their experiences of particular teaching approaches in school might limit or facilitate their studying aspirations; concurrently, less research has specifically focused on and surveyed disadvantaged students. In order to gain more insight, 4780 students were surveyed, covering those in Year 7 (age 11-12 years) and in Year 8 (age 12-13) from schools in England with high proportions of those from disadvantaged backgrounds. Predictive modelling highlighted that the students’ aspirations to study non-compulsory science in the future, and to study the particular subject of chemistry, were strongly associated with their extrinsic motivation towards science (their perceived utility of science, considered as a means to gain particular careers or skills), their intrinsic interest in science, and their engagement in extra-curricular activities. Additionally, their self-concept beliefs (their confidence in their own abilities in science), some teaching approaches, encouragement from teachers and family alongside family science capital also had smaller but still relevant associations.

With the revision of the South African curriculum stoichiometry is taught in Grade ten and eleven and examined in the final matriculation examinations. Learner performance in these questions is generally poor with recommendations that stoichiometry be taught more thoroughly by South African teachers in Grade 10 and 11 and that teachers require professional development in this topic.  This study aimed at developing instruments to measure the quality of teachers’ topic-specific pedagogical knowledge and stoichiometric content knowledge, since content knowledge is considered as a key component in the development of pedagogical content knowledge. Since the concept of pedagogical content was first introduced as a type of knowledge used by teachers to transform their content knowledge into forms that are understood by learners many models and much research into its nature, capturing and measurement has been constructed. Currently pedagogical content knowledge is viewed as a both topic-specific professional knowledge and classroom practice that work together to improve learner understanding of a topic. The focus of this study is on the knowledge aspect of pedagogical content knowledge and the transformation content knowledge through pedagogical reasoning through five knowledge components. These knowledge components include learner prior knowledge, curricular saliency, what makes the topic easy or difficult to understand, representations and conceptual teaching strategies. Reasoning through these five components, it is postulated develops a teachers pedagogical knowledge. This model is referred to as topic-specific pedagogical content knowledge and was the theoretical framework for this study. The design of the instruments followed the rational method for instrument design and was a rigorous process that included framing the big ideas, or unifying principles for teaching stoichiometry. This required an argument for a refined conception of the mole to determine a curricular salient teaching approach for teaching stoichiometry. Since the aim of this study was instrument design, with both qualitative and quantitative aspects a mixed methods approach was used. The designed instruments were validated with a small purposeful sample of practising Grade 11 Physical Sciences teachers and the Rasch statistical model was used to instruments validity and reliability. The Rasch analysis determined that a valid and reliable topic-specific pedagogical content knowledge was developed, adding to literature of the topic-specificity of topic-specific content knowledge as a construct. The Content Knowledge Achievement Instrument was also determined to be a valid instrument to measure stoichiometric content knowledge but yielded only moderate reliability indices. The instruments were used to determine the quality of the participants’ topic-specific pedagogical content knowledge, the participants’ conception of the mole and the quality of the participants’ stoichiometric content knowledge. The quality of the participants’ topic-specific pedagogical content knowledge ranged between basic pedagogical content knowledge and developing pedagogical content knowledge. More than half of the respondents that participated in this study held conceptions of the mole that are inconsistent with the SI definition of the mole. Most of the participants demonstrated a high level of content knowledge despite their conceptions of the mole which generally impacts on their teaching approach, which was found to be mainly algorithmic with a focus on stoichiometric calculations. The relationship between the participants’ measured topic-specific pedagogical content knowledge and content knowledge was shown to be weakly positive and requires further investigation. The findings of this study suggest that the instruments could be used to measure teachers’ topic-specific pedagogical content knowledge and content knowledge in stoichiometry to identify areas for in-service training, or in pre-service training programmes to develop pedagogical content knowledge and, ultimately improve learner performance in the topic of stoichiometry.

The focus of this systematic literature analysis is to provide a comprehensive review of earlier research on the utilisation of 3D printers in chemistry education. The objective is to offer research-based knowledge for developing chemistry education through following research questions: what kind of work has been done in the field of 3D printing in chemistry education; what kind of design strategies have been implemented; how 3D printing has been used in chemistry education research. The data consists of 47 peer-reviewed articles which were analysed via qualitative content analysis using a technological pedagogical content knowledge framework. Theoretical framework was selected because integrating 3D printing in chemistry education requires knowledge of chemistry, technology, and most importantly, pedagogy. Our research indicates that integrating 3D printing begins by analysing current challenges which are reasoned via pedagogical or technological content knowledge-based arguments. 3D printing was used for producing solutions (e.g. physical models) that support working with found challenges. In chemistry education research, 3D printing has mainly been used for printing research instruments; few studies have investigated its effect on learning or students' perceptions towards it. There is a great need for comprehensive student-centred pedagogical models for the use of 3D printing in chemistry education.

We describe biodegradable bridged silsesquioxane (BS) composite nanomaterials with an unusually high organic content (ca. 50%) based on oxamide components mimicking amino acid biocleavable groups. Unlike most bulk BS materials, the design of sub-200 nm nearly monodisperse nanoparticles (NPs) was achieved. These enzymatically degradable BS NPs were further tested as promising imaging nanoprobes.

Symbolic expressions are essential resources for producing knowledge, yet they are a source of
learning difficulties in chemistry education. This study aims to employ social semiotics to analyse
the symbolic representation of chemistry from two complementary perspectives, referred to here
as contextual (i.e., historical) and functional. First, the contextual account demonstrates that
symbolism was introduced to represent compounds according to their elemental composition, to
quantify chemistry, and to explain reactivity. Further to this, the functional analysis shows that
symbolic expressions entail a range of unique grammatical resources to create specialised forms
of knowledge, which cannot be made by natural language alone. It is found that historically the
symbolic representation was not originally directly related to the submicroscopic domain, nor did
it develop sufficient means to offer particulate explanations, although an indirect link could be set
up between Berzelian formulae and the submicroscopic theoretical models. It is also found that
understanding the quantitative aspects is a necessary but not sufficient condition for effective
engagement with the symbolic representation of chemistry. Finally the present study discusses the
pedagogic implications stemming from the social semiotic account of chemical symbolism

Teacher practices are essential for supporting learners in scientific inquiry practices of framing research questions, designing and conducting investigations, collecting data, and drawing conclusions. This study examines instructional practices of two Grade 11 Physical Science teachers engaged in teaching practical investigations. Data were collected from video recordings of teachers' enactment of pre-laboratory, laboratory and post-laboratory practical investigation lessons. Other data sources included video-based classroom observations, teacher and learner interviews, and artefacts, such as teacher handouts, supplemental materials and learner work. The results suggest that when teachers introduce practical investigations, they vary in the practices they engage in as well as the quality of their use of these practices. Implications for teacher practices of scientific inquiry are explored.

Purpose of the study: This study investigates the effect of collaborative metacognitive activities (CMA) on students' socially motivated metacognitive experiences (SMME) during stoichiometric problem-solving. Methodology: This descriptive research employed mixed methods. To document and analyze students' CMA, dual coding process, discourse analysis, and social network analyses were used. There were 18 participants selected purposively and grouped homogeneously based on their academic ability. Main Findings: The findings revealed that CMA affects students' SMME quantitatively in stoichiometric problem-solving across ability groups and chemistry tasks. Successful collaboration occurs when feedback requests and other monitoring responses on the assessment of understanding and strategy influences students' estimates of solution correctness and feeling of satisfaction across ability groups and affects the feeling of difficulty across chemistry tasks. Applications of this study: This study will help teachers design student activities that could capitalize on the advantages of collaborative metacognitive activities to help students achieve successful collaboration during problem-solving activities not only in chemistry but also in the allied fields. Novelty/Originality of this study: This study explains clearly the relevance of CMA and SMME during stoichiometric problem-solving. Moreover, this study elucidated the mechanism of successful and unsuccessful collaboration used by the different groups of students in solving the algorithmic and conceptual chemistry tasks.