Recently, a number of studies have examined the lived experiences of the international teaching assistants (ITAs) in the U.S. classrooms. The findings show that the ITAs face many challenges such as classroom management, instructional, linguistic, cultural and social challenges. Following this line of research, this interview-based study examined…

The flow of electricity from one body to another has been known by man since we first learned how to gather an electric charge. In contrast to conventional wisdom, the process in the general case is not easy to explain. It is different in plasma in the Sun or in your colour TV display, in semiconductors inside your computer or TV set circuits, or…

This study examined how 21 college-level general chemistry students, who had received instruction that emphasized the symbolic level of ionic equations, explained their submicroscopic-level understanding of precipitation reactions. Students' explanations expressed through drawings and semistructured interviews revealed the nature of the…

An electrochemical experiment is presented to illustrate biosorption to second-year and upper-division undergraduate students. The extraction of Cd[superscript 2+], Pb[superscript 2+], and Cu[superscript 2+] by nonliving "Typha latifolia" (cattail) roots can be monitored in real time by potentiometry determinations. The open circuit potential…

A first-year laboratory experiment that utilizes concepts of electrochemical tip etching for scanning tunneling microscopy (STM) is described. This experiment can be used in conjunction with any STM experiment. Students electrochemically etch gold STM tips using a time-efficient method, which can then be used in an instructional grade STM that…

In analytical chemistry classes, the importance of gathering a proper sample for analysis of bulk materials is often addressed only briefly or not at all. Although a number of classroom and laboratory exercises have been developed to illustrate factors that impact error introduced by sampling, they generally do not demonstrate the main goal of…

A survey on the teaching of thermodynamics and transport phenomena in chemical engineering curricula in European and US Universities was performed and results are presented here. Overall, 136 universities and colleges responded to the survey, out of which 81 from Europe and 55 from the USA. In most of the institutions responding at least two…

The ingredient lists of your shampoo, makeup, and moisturizer are likely to include a dizzying number of unknown ingredients. What these ingredients are and do is a mystery to most consumers. However, many cosmetics contain ingredients that are linked to health problems and environmental concerns. While examining every ingredient in your beauty…

An individual's motivational orientation serves as a drive to action and can influence their career success. This study examines how goal orientation toward the pursuit of a graduate degree in physics and chemistry influences later success outcomes of practicing physicists and chemists. Two main categories of goal orientation are examined in this…

In this laboratory experiment, college students are introduced to dynamic combinatorial chemistry (DCC) and apply it to determine the substrate selectivity of acetylcholinesterase (AChE). Initially, the students construct a chemical library of dynamically interchanging thioesters and thiols. Then, AChE is added and allowed to select and hydrolyze…

The reaction kinetics of the iodide-catalyzed decomposition of [subscript 2]O[subscript 2] using the integrated-rate method is described. The method is based on the measurement of the total gas pressure using a datalogger and pressure sensor. This is a modification of a previously reported experiment based on the initial-rate approach. (Contains 2…

An extension of the classic keto-enol tautomerization of beta-dicarbonyl compounds into a kinetic analysis of deuterium exchange is presented. It is shown that acetylacetone and ethyl acetoacetate undergo nearly complete deuterium exchange of the alpha-methylene carbon when dissolved in methanol-d[subscript 4]. The extent of deuteration may be…

In this discovery laboratory, students performed electrophilic aromatic substitution reactions between 1,4-dimethoxybenzene and either 2-methyl-2-butanol or 3-methyl-2-butanol with sulfuric acid as a catalyst. The carbocation from 3-methyl-2-butanol undergoes a hydride shift, and hence, both reactions afford…

The importance of English as a means of communicating chemical information effectively cannot be overemphasized. Ironically, however, using English as a common language of chemistry might hinder nonnative English speakers from actively participating in major chemical communication. To address this problem, South Korea, where English is not an…

Many idiopathic epilepsy syndromes have a characteristic age dependence, the underlying molecular mechanisms of which are largely unknown. Here we propose a mechanism that can explain that epileptic spells in benign familial neonatal-infantile seizures occur almost exclusively during the first days to months of life. Benign familial…