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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.

This study examined the relationship between the time students spend on practice problems and their performance on exams in various chemistry topics, considering their demographics. The researchers divided 91 general chemistry students into three groups based on the time allotted for solving intervention questions: Minimum, Average, and Maximum. The results showed that the Minimum and Average time groups benefited almost equally, but the performance of the Maximum time group declined. This suggests that, while additional practice is beneficial, there could be an optimal amount of time that students should spend on each question. Spending too much time on a single question can lead to mental and emotional fatigue, resulting in a decline in performance. Additionally, the researchers noted variations in performance across different chemistry topics and student groups, and they examined the relationship between student demographics and their problem-solving performances. The study provides recommendations for educators, testing services, and online homework systems to improve the effectiveness of chemistry instruction, highlighting the importance of finding the right balance between practice time and student engagement, and suggesting that a uniform approach to practice problems may not be ideal for every student.

Research into conventional summative assessment methods, such as written exams, has been extensively documented in the literature. However, as academia evolves in response to changing dynamics, there is a growing demand for more robust summative assessment approaches. Oral exams have emerged as a noteworthy form of summative assessment with intrinsic formative qualities, enabling instructors to delve deeply into students’ comprehension within a meaningful learning framework. Considering the constraints imposed by the traditional written examination format during the COVID pandemic, two educators implemented oral assessments in their chemistry courses, one in general chemistry and the other in organic chemistry. This article presents a comprehensive account of their approach, course structure, rubrics, documentation procedures, and the challenges associated with implementing oral exams. Furthermore, the authors offer insights derived from perceived course outcomes, experiences, collaborative efforts, and reflections from this transformative process. Through candid exploration, this article delves into both the potential advantages and the hurdles associated with the adoption of oral exams in chemistry education. It serves as a valuable resource for educators seeking innovative assessment strategies.

The pKa values of water and the hydrogen ion (proton) in water are 14 and 0, respectively. Yet, many textbooks of general, organic, and, to a lesser extent, inorganic chemistry provide the incorrect values 15.74 and -1.74, respectively. This column briefly introduces the long-standing issue of these two different pairs of values, the consequences it bears when teaching general chemistry, and expresses the hope that it may be solved soon.

This investigation sought to elucidate the influence of students' academic legacy on their prior knowledge and course outcomes providing crucial insights for educators who teach general chemistry. This six-semester analysis involved 6,914 students enrolled in classes across nine Texas universities. Explored were personal circumstances associated with students' successes and failures that influenced performance in on- and off-sequence, first- and second-semester general chemistry (Chem 1 and Chem 2). Students' academic legacy based on their categorization as first generation (neither grandparent nor parent/guardian with a 4-year bachelor's degree), second generation (at least one grandparent or parent/guardian with a bachelor's degree), or third generation (at least one grandparent and at least one parent/guardian hold a bachelor's degree) was investigated. Of the students in the dataset 33.8% (n = 2,340) self-identified as Hispanic. Results for Hispanic and non-Hispanic students indicated that first-generation students struggled more with Chem 1 and Chem 2 than students in the other two legacy groups. As students' academic legacy extended, they were more apt to succeed in general chemistry. Second- and third-generation students demonstrated stronger prior high-school chemistry backgrounds and were enrolled in more advanced mathematics courses. As expected, students with stronger academic backgrounds in chemistry and mathematics scored higher on the diagnostic MUST (Math-Up Skills Test), had greater self-efficacy relative to their preparation to succeed, and reported fewer paid work hours. First-generation students on the average entered with lower diagnostic MUST scores, felt less prepared to succeed, and disclosed a greater need to be employed.

When General Chemistry at West Point switched from interactive lectures to guided inquiry, it provided an opportunity to examine what was expected of students in classrooms and on assessments. Learning objectives and questions on mid-term exams for four semesters of General Chemistry I (two traditional semesters and two guided inquiry semesters) were analyzed by the Cognitive Process and Knowledge dimensions of Bloom’s revised taxonomy. The results of this comparison showed the learning objectives for the guided inquiry semesters had a higher proportion of Conceptual and Understand with a corresponding decrease of Factual, Procedural, Remember and Apply learning objectives. On mid-term exams, the proportion of Remember, Understand, Analyze/Evaluate, Factual, and Conceptual questions increased. We found that guided inquiry learning objectives and mid-term exam questions are more conceptual than traditional courses and may help explain how active learning improves equity in introductory chemistry.

In this paper we describe an intervention study on the application of the octet rule. This study was conducted at a German University with students in their first- and second undergraduate year. As repeatedly observed by us before, the evaluation of the study confirmed that the students have difficulties with the application of the octet rule in general, but above all for charged molecules. After an intervention, which consisted of a detailed checklist for the application of the octet rule and training opportunities, the students’ competences increased, especially for the tasks which included charged molecules. Students’ explanations were not as good as expected; the linguistic quality did not increase significantly from pre-to post-test. This is not surprising, because the training of argumentation skills was not part of the intervention. The intended goal, training the application of the octet rule, has been achieved.

This study aimed to examine the views of preservice science teachers on concept map use in a General Chemistry II class. The study was conducted with 47 preservice science teachers. In the study, an interview form grounded on determining their views on concept maps and comprised of open-ended questions, was used as the data collection tool. In analysis of the data acquired, content analysis was performed. As a result of the analysis of the data, the preservice teachers expressed positive views on concept map use. They stated that it might contribute to their learning and increase the permanence of the knowledge learned. Also, they reported that they liked creating concept maps and among the concept map types they usually chose to create hierarchical concept maps. Most of the preservice teachers stated that they had to know the subject related to the concept map very well in order to create concept maps more easily, otherwise they might have a difficulty in the concept map creation process and thus concept maps should generally be used after a lecture. In addition the preservice teachers stated that they intended to use concept maps in their teaching experience. As a result, before concept maps are used in teaching, it is recommended to inform students about the creation of concept maps, to use them for re-purpose in teaching activities, and to include activities containing concept maps in textbooks.

A PROPOSAL FOR ANALYZING CHEMISTRY ISSUES AT ENADE ACCORDING TO THE COGNITIVE LEVEL OF DIFFICULTY. This article aims to present an analysis of the ENADE-Chemistry exam using a taxonomy based on the cognitive operations mobilized to solve the chemistry issues here called as Cognitive Level of Difficulty. In addition to identifying contents in the area of knowledge, skills and competences. All questions from the exams of the years 2011, 2014 and 2017 were analyzed; selected the statistical data present on the reports issued by INEP for four higher-educational institutions (UFRN, UTFPR, UFU and UFAM) and the percentages of the distractors indicated. These data were organized in an excel spreadsheet (database) that helped the comparisons of different variables. As a result, we observed discrepancies when comparing the variables of the ease index and the cognitive level of difficulty for the questions that addressed general chemistry concepts. For example, issues considered very difficult in the easiness rating, but which required low order thinking skills and reciprocally. We consider the proposed taxonomy of analysis of cognitive operations and the database is a tool that can contribute to their courses structure. Furthermore, the proposal can be extended to other areas.

This research endeavored to assess developed and validated a proposed learning module in General Chemistry during the Second Semester, Academic Year 2021-2022 in public secondary schools in Bulacan, Philippines. Teachers play an essential role in validating and evaluation of instructional materials. As facilitators of learning, they must ensure that instructional materials serve their purpose of upholding an effective teaching and learning process. The study aimed to evaluate the proposed Grade 12 General Chemistry learning modules as perceived by Chemistry Experts and Science Teachers in the 12 public secondary schools offering STEM strand in the Division of Bulacan, Philippines. The modules are evaluated based on :(1) content, (2) format, (3) presentation and organization, (4) learning activities, (5) evaluation activities and (6) accuracy and up-to-datedness of information. The demographic profile of 11 Chemistry experts showed that the majority are female, BSED graduates in Physical Science with a doctoral degree in Development Education and 1-12 years teaching General Chemistry subject. Grade 12 Chemistry teachers are mostly females who have bachelor’s degree in Physical Sciences, with master’s units and 1-5 years of teaching Grade 12 General Chemistry in the K to 12 Curriculum. Chemistry experts and science teachers assessed the five modules using descriptive survey method employing quantitative analysis. They both evaluated the proposed learning modules satisfactory in the six dimensions. They did, however, make several suggestions for improving the proposed learning module.

Abstract Objective The application of molecular graphics software as a simple and free alternative to molecular model sets for introductory-level chemistry learners is presented. Results Based on either Avogadro or IQmol, we proposed four sets of tasks for students, building basic molecular geometries, visualizing orbitals and densities, predicting polarity of molecules and matching 3D structures with bond-line structures. These topics are typically covered in general chemistry for first-year undergraduate students. Detailed step-by-step procedures are provided for all tasks for both programs so that instructors and students can adopt one of the two programs in their teaching and learning as an alternative to molecular model sets.

The organization, content and rationale behind the ' Experimental Lecture General and Inorganic Chemistry ' as well as its theoretical ' Consolidation Lecture ' companion as the first contact of students in the B. Sc. program in Chemistry and Chemical Education as well as several others, i.e. Pharmacy, Geosciences, Molecular Medicine and Physics is described. To cope with the multifaceted demands on this first semester lecture series by several faculties, the experimental lecture is attended also by students from other fields. The companion lecture that addresses the advanced needs of chemists, consolidates the content of the experimental lecture by going more into detail and extends on the theories/concepts/reactions. An integrated interplay between experiment and theory is realized in our specially equipped lecture hall.

Abstract Background Engagement with particle-level simulations can help students visualize the motion and interactions of gas particles, thus helping them develop a more scientifically accurate mental model. Such engagement outside of class prior to formal instruction can help meet the needs of students from diverse backgrounds and provide instructors with a common experience upon which to build with further instruction. Yet, even with well-designed scaffolds, students may not attend to the most salient aspects of the simulation. In this case, a screencast where an instructor provides narrated use of the simulation and points students towards the important observations may provide additional benefits. This study, which is part of the larger ChemSims project, investigates the use of simulations and screencasts to support students’ developing understanding of gas properties by examining student learning gains. Results This study indicates that both students manipulating the simulation on their own and those observing a screencast exhibited significant learning gains from pre- to post-assessment. However, students who observed the screencast were more than twice as likely to transition from a macroscopic explanation to a particle-level explanation of gas behavior in answering matched pre- and post-test questions. Eye-tracking studies indicated very similar viewing and usage patterns for both groups of students overall, including when using the simulation to answer follow-up questions. Conclusion Significant learning gains by both groups across all learning objectives indicate that either scaffolded screencast or simulation assignments can be used to support student understanding of gas particle behavior and serve as a first experience upon which to build subsequent instruction. There is some indication that the initial use of the screencast may better help students build correct mental models of gas particle behavior. Further, for this simulation, watching the instructor manipulate the simulation in the screencast allowed students to subsequently use the simulation on their own at a level comparable to those students who had manipulated the simulation on their own throughout the assignment, suggesting that the screencast students were not disadvantaged by not initially manipulating the simulation on their own.

This study aims to describe the development process and determine the feasibility of multiple representation-based textbooks that are designed with a guided inquiry model. The method used in this research is the Research & Development (R&D) with the ADDIE (Analyze, Design, Develop, Implementation, Evaluate) model. Analyze stages are carried out in the form of curriculum analysis, concepts, and learning resources. In the design process, textbooks are made following the guided inquiry learning stages and design the media in the form of images that show multiple representations so that an initial draft is produced. At the Develop stage, draft books are printed and reproduced for validation and revision. The next step of implementation is carried out through a small-scale trial to determine the initial response to the textbook. In the final stage (Evaluation), the textbook on the results of the small-scale trial was revised to be used in the medium-scale trial to get the textbook's final response data. This study involved ten students in the chemical Tadris department in the small group and 29 students in the moderate group. The instrument used was the validation sheet and the language response sheet and the presentation of the textbook. Data of expert validation and trial results were analyzed descriptively and qualitatively in the form of percentages using a Likert scale. The results showed the feasibility of the content, linguistic, presentation, and graphic textbooks, respectively 95.33%, 94.76%, 92.16%, and 92.58%. The suitability of the textbooks with the guided inquiry syntax and multiple presentations was 98.33% each. A small group trial shows that the language aspect gets 84.33 scores, and the presentation aspect is 84.75. After the textbook was revised, the trial results for the medium group showed that the linguistic aspect value was 90.34, and the presentation aspect was 92.59. Overall it can be concluded that the textbooks developed are very suitable for use in learning.

The aim of this paper was to investigate the effect of the use of science, technology, and society (STS) issues through flipped and traditional learning environments on students’ motivation to learn chemistry as well as their chemical literacy (CL). Two freshman engineering classes totaling 89 students taught by the same instructor enrolled in a general chemistry course at a university were the sample of the study. The study had one intervention and one comparison group (CG); the groups were randomly assigned. The intervention group engaged in the STS issues through flipped learning environment while the CG engaged in the STS issues in a traditional setting. A motivation questionnaire was administered to the groups at the beginning and at the end of the treatment; in addition, CL items were administered at the end of semester. The treatment took one semester. Multivariate analysis of variance (MANOVA) was used to compare groups on pre-test scores; then, multivariate analysis of covariance was used to reveal the effect of treatments on motivation, its factors, and CL. The results indicated that utilizing STS issues through the flipped learning environment was superior to traditional STS instruction on increasing students’ overall motivation score, intrinsic motivation, and relevance of chemistry. No significant difference was observed in CL scores. Further studies are suggested to investigate the impact of flipped STS interventions on higher-order thinking skills including socio-scientific reasoning.

The best tutors give a student the appropriate amount of guidance necessary for learning while helping the student stay confident, motivated and focused. So-called intelligent tutoring systems, trying to replicate the discipline-specific and the psychological dimensions of expert human tutoring, require enormous investments and are not accessible to the larger student population. PQtutor (physical quantities tutor) is a free online tutor designed to help students work out homework problems closely related to worked examples. The software is an extension of a free online calculator for science learners and uses problems from an open (free) textbook, making PQtutor accessible in terms of both technology and cost. PQtutor works by comparing student input to a model answer in order to generate prompts for finding a path to the solution and for correcting mistakes. The feedback is in the form of questions from a virtual study group suggesting problem-solving moves such as accessing relevant content knowledge, reviewing worked examples, or reflection on what their answer means. In cases where these moves have been exhausted but the problem remains unsolved, the tutoring system suggests seeking intelligent human help.

A primary motivation for this study was to compare student perceptions and performance within a virtual learning environment to the traditional in-person learning experience for the General Chemistry II course taught during a 5-week summer session at Xavier University of Louisiana, a minority serving institution. The authors present quantitative and qualitative analyses including the comparison of student performance on exams during the COVID-19 remote learning experience with exam performance over a 3-year period of conventional in-person instruction. In this article, student grades, survey feedback, and learning outcomes are outlined. This study was performed to assist the faculty in improving and enriching the course content and its delivery, as they coped with the transition to a virtual learning environment imposed by the COVID-19 pandemic.

The molecule of the week is regularly used by the author in his first-semester course General Chemistry I (Inorganic Chemistry) to illustrate, exemplify, and deepen fundamental aspects and concepts treated in the course. Pure sulfuric acid and its autoprotolysis is used to introduce the concepts of protochemical window and superacidity. The drug Auranofin serves at showing fundamental aspects of gold redox and coordination chemistry and the widely used disinfectant trichlo- roisocyanuric acid (TCICA) exemplifies redox processes with organic compounds.

General Chemistry covers a wide variety of structure-property relationships that rely upon electronic, atomic, crystal or molecular factors. Giving students experimental data will allow them to identify the structure-property patterns as well as identify the limit of predictability of such patterns. “ChemEd X Data” is a web interface designed by the author that facilitates the navigation, filtering and graphical representation of chemical and physical data. It can assist students at identifying trends in structure-property relationships, they can create controlled experiments to test a relationship as well as investigating how different molecular factors may affect a single macroscopic property. In particular, since the site offers unstructured but dynamically searchable data, it is designed to have students learn control of variable strategies (CVS). This paper describes the implementation of a five-step sequence of activities related to structure-property relationships in a General Chemistry semester. ChemEd X Data is used for the open-ended or data-driven steps of this sequence. Student performance is analyzed with the objective of understanding which activities require a higher cognitive skill, as well as identify student previous performances that correlate with success in the activities and in the course in general.

When implementing innovative teaching techniques, instructors often seek to gauge the success of their methods. Proposing one approach to assessing classroom innovation, this study examines the ability of students’ ratings of engagement and instructional practices to predict their learning in a cooperative (team-based) framework. After identifying the factor structures underlying measures of student engagement and instructional practices, these factors were used as predictors of self-reported student learning in a general chemistry course delivered using a team-based learning approach. Exploratory factor analyses showed a four-factor structure of engagement: teamwork involvement, investment in the learning process, feelings about team-based learning, level of academic challenge; and a three-factor structure of instructional practices: instructional guidance, fostering self-directed learning skills, and cognitive level. Multiple linear regression revealed that feelings about team-based learning and perceptions of instructional guidance had significant effects on learning, beyond other predictors, while controlling gender, GPA, class level, number of credit hours, whether students began college at their current institution, expected highest level of education, racial or ethnic identification, and parental level of education. These results yield insight into student perceptions about team-based learning, and how to measure learning in a team-based learning framework, with implications for how to evaluate innovative instructional methods.

General chemistry is a freshman-level class required for most science majors and pre-professional undergraduates. A variety of concepts are introduced in this course; among them, chemical reactions are fundamental, but remain a central topic. The author compared 10 textbooks widely used for college-level general chemistry courses. They all cover the three major classes of chemical reactions: precipitation reactions, acid-base reactions, and oxidation-reduction (redox) reactions. However, significant differences in the way these textbooks present the material may cause confusion and misunderstanding for students, including when they move to upper-level courses. The author suggests a modified reaction classification scheme for general chemistry courses, which will provide students a more complete and nuanced understanding of chemical reactions.

Making a laboratory science course accessible to distance learners requires eliminating certain barriers. This paper describes one semester introductory chemistry courses for science and non-science majors that feature laboratory experiments that students can do at home, using materials readily available from local grocery and hardware stores. Courses using this approach have been offered successfully for several years at the University of Colorado at Denver, Cape Fear Community College and the University of North Carolina at Wilmington, and the laboratory experiences of the distance learners compares favorably with that of traditional students. This paper describes the important features of the distance learning courses, and provides assessment results that indicate the suitability of these experiments as replacement for traditional laboratories.

The students of a General Chemistry class made absorbance measurements in different concentration methylene blue solutions, through the color analysis of solutions pictures. They obtained a calibration curve with a R2=0.9904 that was used for the concentration determination of dye samples exposed to sunlight in variable degradation times with TiO2 as catalyst. The colorimetric method essayed is easy to use and it may be applied in laboratories where a UV-Vis spectrophotometer is not available.

The COVID-19 pandemic in the first quarter of 2020 resulted in the worldwide disruption of teaching and learning in main stream schools and in institutes of higher learning. Singapore was not spared. With the closure of schools in early April, it was imminent that the delivery and assessment of our freshman general chemistry course must be overhauled for the new semester. While the delivery of Home-based Learning (HBL) was a challenge for all educators, it was a mammoth roadblock for chemistry courses because of laboratory classes. Besides being thrusted to learn and use new technology tools for online lessons, instructors also had to quickly explore and design alternative assessments to substitute in-person written examinations and tests. This paper documents the struggles that played out in the decision to implement concept map assessments and “split-half” laboratory classes for safe distancing. Although these interventions are not novel, we confronted tensions as we sought to address academic integrity, administrative guidelines, and our own inadequacy particularly in concept map assessments. In light of positive and negative feedback from both staff and students, lessons were drawn to enhance future implementation and for further research.

A personal account of the development of two University level chemistry books is presented. The account focuses on ways to integrate the traditional branches of chemistry into a textbook that captures the imagination of students and relates chemical principles and fundamental topics to environmental, medicinal, biological and industrial applications. The ways in which teaching methods have changed over two decades and how web-based resources can be used to improve the communication of chemical (in particular structural) concepts are highlighted.

This work shows the results of the implementation of an interactive material, in which presents the contents that are taught in the course in General Chemistry, oriented to the careers in engineering of the University of La Serena, in addition to display and demonstrate in virtual form some of the laws covered in the course. We were able to determine that students improved the understanding of the content, that the information provided is geared to the students of these races, in addition to the application of exercises and explanation in virtual form. The percentage of approval of students compared with previous years remains equivalent, but the notes of approval increased by approximately 10 %. Its concluded that this type of tools are successful to improve the understanding and application of chemistry to the students of engineering.

The aim of this paper was to analyze the historical approaches to the periodic table in general chemistry textbooks used in Brazilian universities in the twentieth century. Textbooks were qualitatively analyzed according to the following criteria: position of the discussion about the periodic table in the book; presence or absence of a specific chapter on the subject; presentation of attempts to classify chemical elements before Mendeleev; presentation of the construction process of the periodic table by Mendeleev; identification of problems in the original table; discussion of Mendeleev's predictions about unknown elements; organization of the periodic table; periodic properties presented and discussed; and the enunciation of the periodic law. The analysis revealed different approaches at specific periods of the twentieth century, from more descriptive approaches to emphasis on attempts to explain the periodic table in terms of atomic orbitals. These changes point to different ways of understanding chemistry during the period studied.

In this paper it is described the use of a group of software, elaborated with didactic objectives, for simulating lab practices and support General Chemistry’s learning at a Cuban university. It is explained how the software were designed so that their visual environment looked like the interior of a chemical laboratory, at the same time, it is monitored the student's interaction with the equipments and instruments according to the objectives expected in the practice. Besides contributing to the saving of resources and care of the environment, the introduction of the software in the process of teaching-learning of General Chemistry allows the students to acquire the necessary abilities to carry out the practices in the real laboratory, since they have the opportunity to repeat the virtual practices as much as necessary. Also, the evaluation is facilitated and instructions for the independent study are included.

This paper aims at analyzing the history of science content of three general chemistry textbooks used in Brazilian universities: the translations of Kotz and Treichel's Chemistry & Chemical Reactivity, Atkins and Jones's Chemical Principles, and Garritz and Chamizo's Química. Results revealed different trends for the inclusion of history of science in chemistry teaching. Kotz & Treichel and Atkins & Jones used history mainly as curiosity and ornament. Garritz & Chamizo adopted the historical approach as one of the organizing axis of their textbook. Nevertheless, the historical content of the three textbooks may be criticized from current historiographical standpoint.

The purpose of this paper is to present a classification criterion for general chemistry experiments departing from a survey of 35 years of the experimental general chemistry discipline at the Chemistry Institute - UNICAMP. It is shown that by considering the most remarkable characteristics of an experiment and classifying it under Conceptual, Fundamental, Methodological or Quantitative criterion, teachers could better develop the discipline plan and prevent a subject superposition. Taking into account the system Fe3+/SCN- , the article also exemplify how is possible to modify an experimental approach and to conceive other procedures with different didactic purposes.

The post-secondary education system in the Province de Québec is quite different from that in the rest of Canada and in many other countries throughout the world. The introduction of a 2-year Collèges d’enseignement général et professionnel (CEGEP) program in 1967 has led to a reduction in the number of years that Quebec students have to spend in both high school and at university. The CEGEP program combines the last year of high school with the first year of a traditional 4-year university program meaning that students living in Quebec must do a 3-year undergraduate degree at the universities, while all other students must do a 4-year degree. Moreover, since almost 50 % of 27 000 undergraduate students at McGill come from other parts of Canada and internationally, this has led to enrolments of about 1000 students in the basic science courses. We present here an overview of how the introductory General Chemistry courses at McGill University are currently being handled so that the students have a meaningful first-year experience.

A concern about students’ conceptual difficulties in organic chemistry prompted this study. It was found that prior knowledge from general chemistry was critical in organic chemistry, but what were some of the concepts that comprised that prior knowledge? Therefore an analysis of four years of organic chemistry quiz data was undertaken. Multiple general chemistry concepts were revealed that are essential prior knowledge in organic chemistry. The general chemistry concepts that were found pose a challenge to organic chemistry instructors who have identified those same concepts as ones they review or consider important in organic chemistry. A review of the literature provides recommendations that address the general chemistry students’ difficulties revealed in this study. Further research, however, is needed to follow through on those recommendations.

This article suggests a sequence of experiments on the preparation, analysis and some photochemical aspects of potassium tris (oxalato) ferrate(III) trihydrate. The sequence of experiments could be carried out in four or five 4-hour laboratory periods. The new part of this article is related to the kinetics studies involving the ambient illumination as well as the use of the cellophane paper of different colors as light filters. The aspects such as quantum yield, light absorption and photochemical reactions are explored in order to illustrate the relationships between the exposure time, light intensity and wavelength range on the photochemical reactions.

The topics developed in the first discipline applied to the freshmen at the Chemistry Institute of UNICAMP are described, along with a discussion of how the program is developed in our days.

In delivering chemistry courses by distance, a key challenge is to offer the learner an authentic and meaningful laboratory experience that still provides the rigour required to continue on in science. To satisfy this need, two distance general chemistry laboratory courses appropriate for Bachelor of Science (B.Sc.) students, including chemistry majors, have been recently developed at Thompson Rivers University. A constructive alignment process was employed which clearly mapped learning outcomes and activities to appropriate assessment tools. These blended laboratory courses feature custom, home experimental kits and combine elements of online and hands-on learning. The courses were designed for flexible continuous enrollment and provide online resources including tutor support, instructional videos, lab report submission, and student evaluation. The assessment of students includes laboratory reports, safety quizzes, reflective journaling, digital photo documentation, and invigilated written and online practical exams. Emphasizing the quality and rigour in these distance laboratory learning experiences allowed both courses to be accepted for B.Sc. transfer credit by other institutions, an important criterion for students. This paper will outline the design and development process of these new blended laboratory courses, their course structures and assessments, and initial student results.

In delivering chemistry courses by distance, a key challenge is to offer the learner an authentic and meaningful laboratory experience that still provides the rigour required to continue on in science. To satisfy this need, two distance general chemistry laboratory courses appropriate for Bachelor of Science (B.Sc.) students, including chemistry majors, have been recently developed at Thompson Rivers University. A constructive alignment process was employed which clearly mapped learning outcomes and activities to appropriate assessment tools. These blended laboratory courses feature custom, home experimental kits and combine elements of online and hands-on learning. The courses were designed for flexible continuous enrollment and provide online resources including tutor support, instructional videos, lab report submission, and student evaluation. The assessment of students includes laboratory reports, safety quizzes, reflective journaling, digital photo documentation, and invigilated written and online practical exams. Emphasizing the quality and rigour in these distance laboratory learning experiences allowed both courses to be accepted for B.Sc. transfer credit by other institutions, an important criterion for students. This paper will outline the design and development process of these new blended laboratory courses, their course structures and assessments, and initial student results.

The goal of this three-year project is to establish a modular and interactive Internet website for the teaching of general chemistry to freshmen students enrolled in a life sciences university program (medicine, biology, possibly pharmacy). Students should become familiar with the basic chemistry concepts needed to understand important life processes and the whereabouts in day-to-day usage of chemical technologies. The idea behind the project, supported by four partner universities (Geneva, Lausanne, Neuchâtel, Fribourg), is to offer a flexible tool to students who have followed very different secondary education programs, some of them having not yet taken any science course. The project aims therefore at optimizing their basic science training during the first year of higher education. A system of online exercises and tests helps the students to assess their understanding of the matter. Video films of live experiments and computer simulations illustrate the main principles and phenomena described in the teaching program. Whenever possible, the teaching aims at an integrated vision of biosciences, as illustrated by some examples using a problem-based approach. The site will offer bilingual (French, English), possibly trilingual (German), teaching and is intended to serve annually 1200–1300 students from the supporting universities.

This paper aims to investigate the presentation of the concept of valence in college-level, general chemistry textbooks published in the USA between the 1890s and the 1940s. The delimited period covers the emergence of theories about atomic structure, electronic distribution and chemical bonding. Transition from the classical concept of valence (as the combining power of a chemical element), which resulted from either the analysis of formulas of compounds or experimental results, into the concept related to the electronic structure of elements, according to which the valence is determined by the number of electrons in the last shell, was observed. In general, valence was presented in textbooks in order to serve as an instrument for the writing of formulas of compounds, and historical approaches to the construction of the concept were not contemplated by the authors.

This work propose the development of an experiment that may be used for the teaching of chemistry for undergraduate students in general, using the analysis of olive oil and soybean oil toward the direct injection electrospray ionization Mass Spectrometry - DI-MS/MS with 18-crown-6 as organic modifier. Firstly, olive oil was analyzed from two different brands, one of reputed brand and the other of popular brand and lower price. Soybean oil of popular brand was also analyzed in order to search possible similarities in the components of these oils and to search adulterations of olive oil with soybean oil. The mass spectra were obtained in positive ion mode of analysis, and allowed us to observe characteristic ions of soybean oil, olive oil, and identify the adulterated olive oil. This simple experiment of easy development may be applied in any institution which has a mass spectrometer with electrospray ionization. In addition, with the use of the experiment, the teacher can illustrate general chemistry concepts such as: molecular mass, preparation of solutions, oxidation, and acid-base reactions.

Understanding chemical reactions conceptually involves recognizing characteristics of observable phenomena and envisioning how atoms, ions and molecules move and interact to cause the macroscopic changes. Our research focuses on the development of effective strategies for designing and presenting visualizations (videos and animations) to assist students with making connections between macroscopic and molecular level behaviors of chemical reactions. Specifically, we study how students, who view videos of a redox reaction that exhibits obvious signs of macroscopic chemical change, can determine which molecular animation of a set of contrasting animations is best supported by its fit with experimental evidence. Herein we describe how we develop our videos and animations, and how students are learning from this animation task. Students who select inaccurate animation models are often enticed by a model that is easier to explain and fits with their understanding of reaction equations. We note that even though students indicate a preference for one animation over another, they often revise their drawn representations to fit with features from multiple animations. With the assistance of eye tracking research, we are gaining a better understanding of what students view and how they make sense of it.

Laboratory is a part of most undergraduate chemistry curricula, however the goals that faculty and students hold have received scant attention. Our research has revealed two broad goals for laboratory learning held by faculty. Students however, hold entirely different goals that may pose obstacles for faculty achieving the goals they have set out. Herein we describe our research and propose methods of bringing these goals into better alignment.