Measuring voltage-current and voltage-power curves of a photovoltaic module is a nice experiment for high school and undergraduate students. In labs where real sunlight is not available this experiment requires a solar simulator. A prototype of a simulator using LED lamps has been manufactured and tested, and a comparison with classical halogen…

With the final objective of using computational and chemometrics tools in the chemistry studies, this paper shows the methodology and interpretation of the Principal Component Analysis (PCA) using pollution data from different cities. This paper describes how students can obtain data on air quality and process such data for additional information…

A one-day laboratory epoxidation experiment, requiring no purification, is described, wherein the students are given an "unknown" stereoisomer of 3-hexen-1-ol, and use [superscript 1]H NMR coupling constants to determine the stereochemistry of their product. From this they work backward to determine the stereochemistry of their starting…

Potentiometric titrations are widely taught in first-year undergraduate courses to connect electrochemistry, stoichiometry, and equilibria and to reinforce acid-base titrations. Students perform a potentiometric titration that is then analyzed to determine analyte concentrations and the solubility product constant of the solid species.

We describe a 2 h introductory laboratory procedure that prepares a novel magnetic antimicrobial activated carbon nanocomposite in which nanoscale sized magnetite and silver particles are incorporated (MACAg). The MACAg nanocomposite has achieved the synergistic properties derived from its components and demonstrated its applicability as an…

Semiconductors are an important class of materials; preparing ZnO nanorods allows semiconducting properties to be easily observed. The week before lab, groups of four students take 15 min to setup two fluorine-doped tin oxide glass (FTO) slides in a zinc nitrate and hexamethylenetetramine solution stored at 90°C until the next lab. Hexagonal ZnO…

Recent science reform documents have called for incorporating authentic scientific discourse into science classes as engaging in discourse has shown to result in numerous benefits. Whether these benefits are observed in students depends upon the quality of the discourse in which they engage. However, characterizing the quality of student-student…

Tetrakis(4-sulfonatophenyl)porphyrin (TSPP) was immobilized on patterned paper and used as a sensor for heavy metal ions in an advanced organic chemistry course. The resulting sensor could detect Hg[superscript 2+] and Cd[superscript 2+] ions colorimetrically, while Cu[superscript 2+] ion resulted in fluorescence quenching, thus demonstrating a…

Conceptual models have long served as a means for physical geographers to organize their understanding of feedback mechanisms and complex systems. Analytical reasoning provides undergraduate students with an opportunity to develop conceptual models based upon their understanding of surface processes and environmental conditions. This study…

In the undergraduate curriculum, chemistry and sustainability connect easily and well. Topics in chemistry provide instructors with opportunities to engage students in learning about sustainability; similarly, topics in sustainability provide instructors with opportunities to engage students in learning chemistry. One's own college or university…

This paper reports observations that show a significant effect of class meeting time on student evaluations of teaching for an introductory college physics class. Students in a lecture section with an early-morning meeting time gave the class and instructors consistently lower ratings than those in an otherwise nearly identical section that met an…

We all know that we must improve the quality of teaching in science at all levels. Not only physicists but also many students from other areas of study take the introductory physics courses in college. Physics introductory laboratories (labs) can be one of the best tools to help these students understand applications of scientific principles that…

A series of laboratory experiments were developed to introduce first-year chemistry students to nanoscience through a green chemistry approach. Students made and characterized the stability of silver nanoparticles using two different methods: UV-visible spectroscopy and dynamic light scattering. They then assessed the ecotoxicity of silver…

Several concept inventories have been developed to elicit students' alternative conceptions in chemistry. It is suggested that heuristic reasoning may bias students' answers in these types of assessments toward intuitively appealing choices. If this is the case, one could expect students to improve their performance by engaging in more analytical…

In the context of what are often highly compartmentalised curriculum requirements, this article considers the cyclical nature of the acquisition and transfer of knowledge in the education system in relation to those questions that transcend individual subjects as set out in traditional curriculum divisions. It also considers the detrimental…