Basic Chemical Concepts Research Articles

El manejo conceptual en química a través de redes sociales / Conceptual management in chemistry through social networks

El siguiente artículo tiene como objetivo fundamental el reconocimiento de la incidencia que tiene el uso de las redes sociales, específicamente Twitter, en un rol mediador en el manejo de conceptos básicos de Química en el bachillerato venezolano. La aproximación a este manejo se hizo desde el análisis del contenido de las interacciones que por recurrencia de unidades lingüísticas de referentes se produjeron en las intervenciones de los estudiantes dentro de la red social con la intervención en estas interacciones del e-moderador. Los hallazgos develan claramente la afinidad del estudiante en el uso de redes sociales y herramientas tecnológicas, la comunicación entre pares y la saturación de contenidos permitiendo considerar esta estrategia en la enseñanza de conceptos por lo innovador y afín que se hace con los actores que en ella intervienen y el mantenimiento del concepto de acuerdo a lo establecido en los libros especializados de consulta.

Early Chemistry Misconceptions: Status and Implication on Quality of Primary Education in Ethiopia

Misconceptions towards basic chemistry concepts have been identified at all level of chemistry education in recent studies. Such set of early misconceptions about very basic chemistry concepts were even found to be reflected by pre service and experienced in-service teachers. This implies that numerous set of chemical misconceptions kept cycling in the entire educational system. As a result, the entire science educational system is being blamed of producing learners with numerous misconceptions and low conceptual understanding. In fact, the alarmingly declining students’ performance in regional and national examination in Ethiopia (NOE, 2010), for example, could be an indicator of this situation. Moreover, such quality threatening issues are not getting fair stakeholders’ emphasis especially in Ethiopia. It was aimed, therefore, to discuss the status of early misconceptions and its implications. Article visualizations:

A Pharmacology-Based Enrichment Program for Undergraduates Promotes Interest in Science.

There is a strong need to increase the number of undergraduate students who pursue careers in science to provide the "fuel" that will power a science and technology-driven U.S. economy. Prior research suggests that both evidence-based teaching methods and early undergraduate research experiences may help to increase retention rates in the sciences. In this study, we examined the effect of a program that included 1) a Summer enrichment 2-wk minicourse and 2) an authentic Fall research course, both of which were designed specifically to support students' science motivation. Undergraduates who participated in the pharmacology-based enrichment program significantly improved their knowledge of basic biology and chemistry concepts; reported high levels of science motivation; and were likely to major in a biological, chemical, or biomedical field. Additionally, program participants who decided to major in biology or chemistry were significantly more likely to choose a pharmacology concentration than those majoring in biology or chemistry who did not participate in the enrichment program. Thus, by supporting students' science motivation, we can increase the number of students who are interested in science and science careers.

Discovering More Chemical Concepts from 3D Chemical Information Searches of Crystal Structure Databases

Three new examples are presented illustrating three-dimensional chemical information searches of the Cambridge structure database (CSD) from which basic core concepts in organic and inorganic chemistry emerge. These include connecting the regiochemistry of aromatic electrophilic substitution with the geometrical properties of hydrogen bonding interactions to the ring, the gauche conformational effect in 1,2-disubstituted ethanes, and square planar versus tetrahedral coordination in four-coordinate transition metals. The searches take only a short time and can be readily incorporated into a variety of teaching environments.

Teaching microbiology to undergraduate students in the humanities and the social sciences

This paper summarizes my experiences teaching a 28-hour course on the bacterial world for undergraduate students in the humanities and the social sciences at the Hebrew University of Jerusalem. This course was offered in the framework of a program in which students must obtain credit points for courses offered by other faculties to broaden their education. Most students had little biology in high school and had never been exposed to the basics of chemistry. Using a historical approach, highlighting the work of pioneers such as van Leeuwenhoek, Koch, Fleming, Pasteur, Winogradsky and Woese, I covered a broad area of general, medical, environmental and evolutionary microbiology. The lectures included basic concepts of organic and inorganic chemistry necessary to understand the principles of fermentations and chemoautotrophy, and basic molecular biology to explain biotechnology using transgenic microorganisms and molecular phylogeny. Teaching the basics of microbiology to intelligent students lacking any background in the natural sciences was a rewarding experience. Some students complained that, in spite of my efforts, basic concepts of chemistry remained beyond their understanding. But overall the students' evaluation showed that the course had achieved its goal.

Teaching large undergraduate chemistry classes: A challenge or an opportunity

Teaching introductory modules and classes of undergraduate programmes can present a number of subjective and objective challenges. Objective challenges include a high degree of variation in students’ prior learning experiences combined with a high student-teacher ratio. Subjective challenges include the transitional changes which first year students undergo that include cognitive, affective and physiological changes as they make the leap from the often small and secluded secondary-level environment to the all-consuming tertiary-level environment. For introductory chemistry modules, such as General Chemistry, the pertinence of these challenges can have negative repercussions on students’ acquirement of basic chemical concepts in first year which could inherently go on to hinder their successful progression through their third-level education. In an effort to tackle the challenges posed against effective learning in General Chemistry modules, this exploratory research study set out to understand how the potential incorporation of a new approach to teaching and learning would be received by the three main cohorts involved. The attitudes and recommendations of undergraduate students, post-graduate students who have a role as laboratory demonstrators and module leaders towards the potential incorporation of Student-Inquiry activities and laboratories into General Chemistry were investigated. All three cohorts welcomed the incorporation of Student-Inquiry as part of the approach to teaching and learning. While the researchers and module leaders had an initial awareness of the challenges that come with teaching General Chemistry, little was known of the potential significance of the opportunity which lay amongst these challenges.

Chemical Thermodynamic Concept Mastering by Chemistry Students

The ruling objective of our research is to assess the grasp by students (Option: SMC) of certain chemical thermodynamic concepts that are being learnt in S2 as well as ensure the interpretation of certain organic chemistry phenomena. Our aim is also related to highlighting conceptual difficulties encountered by students. For this end, we conducted an evaluation test for the students of Ben M'sik Science Faculty option: SMC (S4, S6, Master and Doctorate). This test consists of seven questions that we have selected in such a way as to secure objectivity, non-redundant and providing a feedback as to the degree of mastering chemical thermodynamic concepts by students. In order to expand our database revealing the students conception of the thermodynamic chemistry concepts, we considered examining the answers to a question related to the first test (Option: SMC, level S2). So, we examined 956 exam papers. This number represents the total number of examinees. The result showed a flaw in the grasp of certain basic concepts of thermodynamic chemistry studied in S2. This problem was noticed at a variety of levels of studies (S2, S4, S6, Master's degree, Doctorate). Therefore, students move from one level to another carrying with them weaknesses which hinder their future learning.

ENHANCING SCIENTIFIC LITERACY: A RESOURCE FOR TEACHERS

The standard science curriculum is meant to familiarize students with basic concepts in biology, chemistry, and physics. We do not dispute the necessity of this – indeed, a strong grasp of the fundamentals will facilitate the understanding of intermediate and advanced topics later on. Unfortunately, the evaluative approaches in these courses often misinform students of what it means to be a scientist. Students, especially those interested in biology, may be tempted to correlate scientific potential with the ability to retain and recall information for an exam. But that’s not science. As a professor once said at a first-year biology seminar, “We do a good job of teaching you the ‘what’. But we gloss over the ‘how’and the ‘why’.”

Importance of Computer Assisted Teaching & Learning Methods for Chemistry

Understanding the basic concepts of chemistry is very important for the students of secondary school level and university level. The Computer Assisted Teaching and Learning (CATL) methods are marked by the usage of computers in teaching and learning processes. Usage of WORD, EXCEL, POWERPOINT, ACCESS, PHOTOSHOP etc., as well as the use of specialized packages such as CHEMDRAW, SCIFINDER etc., can be worth mentioning. The role of internet in feeding the thirst of students is comparably far better than the classroom teaching. By the use of CATL methods, students can acquire high quality of mental models.

SỬ DỤNG PHƯƠNG PHÁP BÀN TAY NẶN BỘT ĐỂ NÂNG CAO CHẤT LƯỢNG CÁC BÀI DẠY HÌNH THÀNH KHÁI NIỆM HÓA HỌC CƠ BẢN Ở TRƯỜNG TRUNG HỌC CƠ SỞ

SỬ DỤNG PHƯƠNG PHÁP BÀN TAY NẶN BỘT ĐỂ NÂNG CAO CHẤT LƯỢNG CÁC BÀI DẠY HÌNH THÀNH KHÁI NIỆM HÓA HỌC CƠ BẢN Ở TRƯỜNG TRUNG HỌC CƠ SỞ

Representational competence in chemistry: A comparison between students with different levels of understanding of basic chemical concepts and chemical representations

AbstractRepresentational competence is defined as “skills in interpreting and using representations”. This study attempted to compare students’ of high, medium, and low levels of understanding of (1) basic chemical concepts, and (2) chemical representations, in their representational competence. A total of 411 Form 4 science students (mean age = 16 years) from seven urban secondary schools in Malaysia participated in this study. Data were collected from three instruments namely the test of chemical concepts, the test of chemical representations, and the test of representational competence. The Statistical Package for the Social Sciences was used to analyze the data. Findings showed students with a high level of understanding of (1) chemical concepts and (2) chemical representations had significantly higher overall level of representational competence compared to both the medium and the low groups, at p < 0.001. However, students with medium and low levels of understanding of (1) chemical concepts and (2) ...

Assessing the status of fundamental chemistry knowledge Using a visually displayed chemistry diagnostic test

Students in the classroom may possess varying levels of knowledge and understanding of fundamental chemical concepts so it is necessary to ascertain if any misalignment exists with their expected prior knowledge; if left un-addressed, such misalignment may create difficulties for students beyond the first year of their undergraduate study. The aim of this initial diagnostic test study is to assess students' knowledge of basic concepts in chemistry that underpin the science of patient safety in pharmacy practice using a novel approach which enables a variety of question types. Adiagnostic test using Microsoft PowerPoint© consisting of 40 individually timed questions was presented to an entire cohort of Master of Pharmacy (MPharm) degree programme undergraduate students in both the first year (n = 163) and third year (n = 118). The questions ranged from basic chemical nomenclature to more complex areas such as stereochemistry. Our results showed that the third year undergraduates performed significantly better than those in their first year (p ≤ 0.004) with both cohorts performing well in the basic questions such as recognition of elements and bonding. However, a more in-depth analysis of the questions indicated areas such as chemical structures and mole calculations that caused difficulty for both cohorts. This test highlights problem areas in fundamental chemistry concepts which students find difficult either tograsp or to solve, and as such it serves as a useful diagnostic tool enabling a more targeted approach to teaching.

ChemInform Abstract: Metal‐Free Hydrogenation of Unsaturated Hydrocarbons Employing Molecular Hydrogen

AbstractReview: [41 refs.

Relativistic calculations of magnetic resonance parameters: background and some recent developments

This article outlines some basic concepts of relativistic quantum chemistry and recent developments of relativistic methods for the calculation of the molecular properties that define the basic parameters of magnetic resonance spectroscopic techniques, i.e. nuclear magnetic resonance shielding, indirect nuclear spin-spin coupling and electric field gradients (nuclear quadrupole coupling), as well as with electron paramagnetic resonance g-factors and electron-nucleus hyperfine coupling. Density functional theory (DFT) has been very successful in molecular property calculations, despite a number of problems related to approximations in the functionals. In particular, for heavy-element systems, the large electron count and the need for a relativistic treatment often render the application of correlated wave function ab initio methods impracticable. Selected applications of DFT in relativistic calculation of magnetic resonance parameters are reviewed.

Metal‐Free Hydrogenation of Unsaturated Hydrocarbons Employing Molecular Hydrogen

The metal-free activation of hydrogen by frustrated Lewis pairs (FLPs) is a valuable method for the hydrogenation of polarized unsaturated molecules ranging from imines, enamines, and silyl enol ethers to heterocycles. However, one of the most important applications of hydrogenation technology is the conversion of unsaturated hydrocarbons into alkanes or alkenes. Despite the fast development of the FLP chemistry, such reactions proved as highly challenging. This Minireview provides an overview of the basic concepts of FLP chemistry, the challenge in the hydrogenation of unsaturated hydrocarbons, and first solutions to this central transformation.

Alcohol Pharmacology Education Partnership: Using Chemistry and Biology Concepts To Educate High School Students about Alcohol.

We developed the Alcohol Pharmacology Education Partnership (APEP), a set of modules designed to integrate a topic of interest (alcohol) with concepts in chemistry and biology for high school students. Chemistry and biology teachers (n = 156) were recruited nationally to field-test APEP in a controlled study. Teachers obtained professional development either at a conference-based workshop (NSTA or NCSTA) or via distance learning to learn how to incorporate the APEP modules into their teaching. They field-tested the modules in their classes during the following year. Teacher knowledge of chemistry and biology concepts increased significantly following professional development, and was maintained for at least a year. Their students (n = 14 014) demonstrated significantly higher scores when assessed for knowledge of both basic and advanced chemistry and biology concepts compared to students not using APEP modules in their classes the previous year. Higher scores were achieved as the number of modules used increased. These findings are consistent with our previous studies, demonstrating higher scores in chemistry and biology after students use modules that integrate topics interesting to them, such as drugs (the Pharmacology Education Partnership).

Fact or Fiction? General Chemistry Helps Students Determine the Legitimacy of Television Program Situations

A large number of students in chemistry courses are thinking about pursuing careers in the health professions. We used a segment from the popular TV show, Bones, to illustrate how basic chemical concepts can help them solve complex physiological and medical problems. Many students have found the use of the Bones video clip engaging, and appreciated seeing the connection of chemistry to “real-world” situations. This presentation is intended to take chemistry out of the mundane classroom setting and present it in the context of a thrilling (albeit highly improbable) life-or-death scenario.

ConfChem Conference on Educating the Next Generation: Green and Sustainable Chemistry—Chemistry of Sustainability: A General Education Science Course Enhancing Students, Faculty and Institutional Programming

This paper describes a collaborative project to design and teach a general education science course, Chemistry of Sustainability. Our goal was to show how chemistry plays a central role in addressing the grand challenges of protecting the environment and human health by developing the knowledge and tools that meet our basic needs for energy, clean water, and consumer products. Course content was designed using a case-study approach that illustrates how basic chemical concepts including atomic structure, bonding, intermolecular forces, and reactivity are applied to address environmental issues. The cases tapped faculty research expertise and addressed topics such as renewable energy, sustainable consumer products, bioplastics, clean water, and nanoscience. Because sustainability is an interdisciplinary activity, we illustrated how life-cycle assessment and the principles of green chemistry can be used to provide sustainable chemical solutions. A surprising outcome of this project was the breadth and significance of the impacts on our students, faculty, and institution. This communication summarizes one of the invited papers to the ConfChem online conference Educating the Next Generation: Green and Sustainable Chemistry, held from May 7 to June 30, 2010 and hosted by the ACS DivCHED Committee on Computers in Chemical Education (CCCE).

Basic concepts in medicinal chemistry (book review)

Basic concepts in medicinal chemistry (book review)

Emil Zolotoyabko, Basic Concepts of Crystallography

Emil Zolotoyabko's book is an excellent textbook for courses on both geometric/structural and physical crystallography. There are approximately 300 pages with nearly 200 illustrative color figures and an index. The recommended list for general reading comprises references to 17 relevant and well known books as well as to the Powder Diffraction File of the International Center for Diffraction Data. The title of the book and its subtitle are well chosen to represent the whole content of the book. Somewhat unusual for a crystallography text book at the chosen level, the introductory chapter puts geometric/structural and physical crystallography in the wider context of symmetries in nature. The heuristic value and generality of symmetry arguments are illustrated by mentioning that the conservation laws of linear momentum, energy, and angular momentum all follow directly from the homogeneity of space and time. The degeneracy of quantum mechanical states, their lifting by the breaking of symmetries of a confining potential, and selection rules also illustrate the universality of symmetry considerations. This referee feels that this kind of an introductory treatment and the immediately following assertion that “our task within this book is much more modest: to describe the symmetry of crystals and to show how and to what extent symmetry considerations can be used for determining the physical properties of crystals” are bound to impress any reader so that there will probably be many serious students of Emil Zolotoyabko's text book. The next six chapters cover (in 50 pages) crystallographic basics such as direct and reciprocal space as concepts, crystallographic calculations, and the stereographic projection. Reciprocal space is also explained from the physical applications point of view. A nice didactic device is the declaration of four of these chapters as providing the “Language of crystallography” (by making this phrase part of the chapter headings). This will hopefully entice readers to review first all of the “language needed” for the comprehension of the latter parts of the book. The following eleven chapters deal briefly with atomic packings and coordination numbers, i.e. very basic crystal chemistry concepts, as well as comprehensively with the symmetries of crystals (in 115 pages) all the way up their representations in the International Tables. After the initial dealing with individual point symmetries and the introduction of point symmetry groups and Bravais lattices, space groups are derived. Point group mm2 and the Bravais lattices of the orthorhombic crystal system are chosen as examples for the derivation of all of the<?brk?> 22 space groups that their combination entails. This is a very good exercise for the serious student. Seven chapters are left to cover the basics of crystal physics. These chapters utilize the tensor formalism extensively and provide examples of physical property descriptions up to the forth tensor rank. The examples are ferroelectricity, dielectric permittivity, birefringe effects, piezoelectricity, stress/strain and the elastic moduli. Neumann's and Curie's symmetry principles are utilized to “build bridges” between the crystal physics part of the book and the preceding discussions on crystal symmetries. The differences between the propagation of acoustic and electromagnetic waves in crystals are also highlighted. The final chapter is on twinning from both the symmetry and physical properties points of view. All in all, a very nice textbook indeed.