Volume 6, Issue 3

Teaching hydrogen bridges (H-bridges) in introductory chemistry courses is either oversimplified or dogmatically taught; the heuristic that ‘only fluorine, oxygen and nitrogen (FON) form H-bridges’ is commonly used, for example. This rule limits choices, does not match reality, and does not clarify the difference between H-bridge donors (HBD) and H-bridge acceptors (HBA) nor intermolecular versus intramolecular cases. Hydrogen fluoride is a significant HBD but a poor HBA. Oxygen is not always an HBD or HBA. Ammonia is a significant HBA but a poor HBD. There are many examples of H-bridges that do not contain these three elements. All examples of H-bridges should be shown in a way to provide symbolic and molecular structures. Is it necessary to ‘explain’ H-bridges in introductory classes? We conclude not, but it might be necessary to increase the total amount of time to present the material so that students do not rely on superficial rules.

The study aims to explore the implementation of stepwise inquiry in chemistry education. The levels of inquiry used range from structured inquiry (level 1) to guided inquiry (level 2). The research design involved methods of analyzing the implementation of inquiry levels, assessing the ability to answer questions, engage in critical thinking, and gather student responses. The research sample consisted of 73 students studying biochemistry. A total of 14 groups, each containing 5–6 members, were involved in this research. The research results show that six groups (SG) successfully followed the investigation process at the inquiry steps, while eight groups were unsuccessful (UG). The average scores of the sub-skills collaboration, communication, data collection, use of equipment, and implementation of experimental design were the highest compared to other subskills. The stages of interpreting problems, observation, experimental design, formulating hypotheses, data analysis, and developing conclusions are still in progress and are classified as low. The SG group had an average N-Gain critical thinking score higher than the UG group ( p  < 0.05). The analysis of the ability to answer questions and think critically shows that the category of developing hypotheses and analyzing arguments had the lowest ability to respond compared to other indicators.

In STEM higher education, lecturers need to assist learners in constructing understanding of complex scientific concepts by employing relevant teaching methods, tools, and technologies. A continuous professional development (CPD) of academic teaching staff in teaching and learning is indispensable to keep up with the development of STEM. Using a cascade-like approach in continuous professional development in teaching and learning, where lecturers are involved bottom-up as CPD-Ambassadors, makes it possible to address relevant STEM-specific teaching and learning issues and continuously improve teaching practice. At three international STEM-CPD Summer Schools for CPD-Ambassadors, the CPD-Ambassadors developed fifty CPD-User cases about organising professional development in teaching and learning at their own higher education institutions and promoting the importance of CPD in their local context. The analysis of the CPD-User cases shows that the most frequently addressed teaching competencies and attitudes foster student-centred teaching approaches based on constructivist educational views. A relationship is found with previously defined generally important teaching competences and attitudes for higher STEM education. The results indicate that a cascade-like, discipline oriented continuous professional development approach through CPD-Ambassadors is a promising approach in improving university teaching practice.

In a society heavily influenced by technological advancements, developing scientific and technological literacy among young people is essential. Along these lines, this research describes a STEM activity developed to promote the teaching of chemistry content related to the solubility of potassium nitrate in water. It also facilitated the mastery of technological skills such as programming Arduino microcontrollers and using Microsoft Excel as tools for automatic data acquisition and analysis. Eighty pre-university Chemistry students participated in this research. This pedagogical approach was divided into three main stages: (1) preliminary research on components used in the experimental apparatus; (2) introduction to the assembly of electrical circuits and Arduino programming; (3) experimental investigation of the dependence of potassium nitrate solubility on temperature. The activity allowed the students to successfully achieve the proposed chemistry learning objectives while mobilizing other scientific and technological knowledge and skills. Despite the students’ limited prior knowledge of programming and electronics, as well as their limited proficiency in data analysis software, the integration of programming in the Chemistry class proved to be a differentiating factor with a highly positive impact, particularly in terms of motivation and interest among most students.

This study analyzed third-year undergraduate Chemistry major students’ drawings and written explanations of substitution reactions. Seventy (70) students were purposively selected for this study. The main data collection instrument was a diagnostic test and students’ responses were analyzed using deductive coding. The study aimed to unearth students’ conceptual understanding and difficulties on substitution reactions to provide significant insights into improving teaching strategies and learning outcomes. The findings revealed that: 1. Students were more familiar with S N 2 reaction mechanisms and could answer questions on S N 2 reaction mechanisms better than S N 1 reaction mechanisms; 2. Students’ use of ‘chemical vocabulary’ did not translate into an understanding of electron movement and causal mechanistic explanation; 3. About 97 % of the students who gave a correct/partially correct description provided a description of what was happening in the reaction without any further explanation of why the reaction occurred; 4. Students had a slightly better understanding of drawing the correct mechanisms than providing accurate explanations. This study recommends that, in teaching organic reaction mechanisms, instructors should emphasize on electron-pushing formalisms and explain how and why reactions occur to encourage mechanistic thinking in students. Also, students should be given ample practice in organic reaction mechanisms to improve mastery.

The research aims to develop an AR app as a learning tool to facilitate first-year university students in comprehending the concept of the chemical properties and investigate students’ performance in understanding the concept of the chemical properties of main group elements. The app was developed using Unity, Vuforia, Canva, and Blender. A mixed method was employed in the R&D adopting ADDIE development model. Twenty-two students of chemistry education department at a state university in Aceh, Indonesia participated in the need analysis and implementation stage. The data was collected through questionnaires, and a system usability scale. The students’ performance was evaluated through online Quizizz platform. The findings reveal a strong consensus among students regarding the necessity of AR for comprehending chemistry concepts. The students responded positively to the app’s attractiveness, ease of use, impact on their learning experience, alignment with teaching materials, and markers quality, yielding a mean score of 91.8 %. The application is ease to use with a SUS score of 84.9. The N-Gain score indicates positive impact to the students’ performance. AR app of periodic properties of elements demonstrates feasibility and serves as a viable alternative teaching tool for the concept of periodic properties of elements.

Microplastics are now ubiquitous in the environment and are even considered “technofossils” of the Anthropocene. Given their omnipresence and potential impact, identifying and analyzing these particles becomes increasingly crucial. Novel approaches suggest density gradient centrifugation for simultaneous extraction and fractionation of microplastic particles based on their plastic-specific densities. In this article we describe a cheap and harmless experimental setting to fractionate microplastic particles by density gradient centrifugation. An innovative low-cost Do-It-Yourself (DIY) gradient maker using Luer-Lock syringes is presented. With this gradient maker it is possible to produce density gradients with water and sucrose solutions, covering a density range of 1.00–1.32 g/cm 3 , as well as with water and saturated potassium carbonate solutions, covering a density range of 1.06–1.53 g/cm 3 . The separation performance was tested with the most broadly used plastics polyamide, polyurethane, polycarbonate, polyethylene terephthalate and polyvinylchloride. Both density gradients show centrifugation stability and clear banding patterns after centrifugation. Due to its cheap and easy-to-build-easy-to-use nature, this experimental setting for microplastic fractionation by density gradient centrifugation offers an approach for schools not only to address the microplastic problems, but also to integrate new methods of microplastic analysis in upper secondary school laboratories.

Spectroscopy has held a pivotal role in advancing our comprehension of chemistry, dating back to its inception by Robert Bunsen and Gustav Kirchhoff. Nonetheless, access to advanced spectrometers remains restricted, particularly in high schools within developing nations. In this laboratory experiment, students were guided to fashion a spectrometer using reusable materials. This uncomplicated contrivance facilitated the exploration of emission and absorption spectroscopy, acquainting students with atomic spectra marked by electronic transitions, yielding line spectra. Conversely, molecules display not solely electronic transitions, but also vibrational and rotational shifts within chemical bonds, culminating in band spectra. Mobile phone cameras were enlisted as detectors. Captures of sodium and copper atoms emitting light in the course of a flame test, as well as depictions of molecular entities (copper sulphate pentahydrate and potassium permanganate aqueous solutions) absorbing light, were transmuted into the RGB (Red-Green-Blue) color model channels. The learning outcomes exhibited that 86 % of the students successfully discerned between an atomic spectrum and a molecular spectrum. Furthermore, 93 % of the students indicated that the incorporation of mobile devices in fostering scientific comprehension effectively seized their attention, resulting in heightened levels of engagement.

The study aims to explore how students perceive the use of interactive computer simulations (ICS). The mixed-method approach under a converging design was employed to collect quantitative and qualitative data. A sample of 160 participants were purposively selected. The questionnaire consisted of four sections, including Behavioral Intention to Use, Attitude Toward Usage, Usefulness, and Perceived Ease of Use. The collected data was analyzed in MS Excel. 83 % of participants believed that their learning experience has improved and become easier. Moreover, a significant number of students 79 % expressed high perceptions towards the ease-of-use ICS in the teaching and learning process, and 77 % demonstrated a strong positive attitude towards the usage. Additionally, 76 % had a highly positive perception of their behavioral intention to use ICS in their chemistry learning. However, 39 % of students expressed low perceptions of ease of use of ICSs due to a lack of basic computer skills. In general, the findings show positive significance in students’ perceptions toward the use of ICSs in teaching and learning chemistry. The study recommends that ICSs should be used to supplement chemistry education.

High school chemistry teachers typically share a passion to engage students with hands-on practical experiences. However, teachers worldwide face similar challenges of lack of time and resources for laboratory activities. National standards and traditions can also constrain and dictate the level and content of school chemistry practical experiences. In recent years, some national curricula have included a growing focus on the relevance of chemistry to sustainability and environmental issues. Until now, little has been known about what practical activities teachers actually do with their students, and whether practical activities concerning green and sustainable chemistry are being implemented in schools. In this project, we aimed to determine a baseline of teacher perspectives – how often they run practical activities with their students, what factors are important when choosing a practical activity, what barriers they face in running practical activities, and whether their activities relate to sustainability. This was approached through a major international survey of in-service high school chemistry teachers conducted in over 35 local languages in over 60 countries. Here, we present the initial stages of the project: design of the survey, recruitment of country coordinators, translation, and the implementation process.

A program for writing words (or personal names) by combining chemical element symbols is developed in the context of classroom activity to introduce the periodic table, properties of elements, and periodic trends. We provide multiple examples and possible ideas to improve student engagement and create an inclusive environment in the classroom. Common confusions and mistakes made when learning the periodic table are tabulated and discussed. In addition to spelling words and creating graphics using element symbols, the program can display and print out properties of elements as part of the word-building game.

The dualities of benzene derivatives often make basic organic chemistry challenging for students. This includes the relationship between full structural and line-angle formulas, the distinctions between preferred and systematic IUPAC names for benzene derivatives, and the nuances between ortho -, para -, and meta- directors. To effectively demonstrate these dualities of benzene derivatives, we have designed a range of teaching aids rooted in the folk toy, Jacob’s ladder. This paper presents lectures designed for advanced placement high school students and nonchemistry majors, employing this innovative series of Jacob’s ladder-based teaching aids. The majority of students found the lecture engaging, and many developed a comprehensive understanding of the dualities of benzene derivatives.

The conversion from line-angle formula to chemical formula often poses a challenge for first-year nonchemistry majors. To address this, the authors developed an engaging exercise lecture that encompasses the conversion process and related chemistry concepts, including molecular weight and elemental analysis. Initially, the instructor reviews basic chemistry concepts with the students. Subsequently, students construct a NanoKid structure model using transistors and red LEDs connected by plastic tubes, representing carbon and oxygen atoms, respectively. By referencing their models, students identify the chemical formula of NanoKid, calculate its molecular weight, and perform elemental analysis under the guidance of the instructor. Additionally, they estimate the scale of the NanoKid model relative to the actual NanoKid molecule. The exercise promotes peer review among students and is completed within approximately 45 min. A post-lecture questionnaire revealed that the exercise was well-received by the students.