In any demonstration to students, producing light and sound usually ensures interest and can enhance understanding and retention of the concepts involved. A guided inquiry (Predict, Observe, Explain: POE) approach was used to involve the students actively in their learning about the explosive combustion of fine flour particles in air in the…

The idea of expressing the hydrogen-ion concentration on a log arithmetic scale was presented by S. P. L. Sorensen in 1909. The symbol that he used was the letter p and a smaller H appearing almost as a subscript. Typographical convenience led journals to adopt the current symbol. It has been common to assume that the p represented a word such as…

Learning communities provide connections between disciplines in a supportive environment and allow students to participate in two or more linked courses in small groups. Undergraduate institutions that have incorporated learning communities in their curriculum have experienced positive effects from this approach. Learning communities have the…

Microwave heating enhanced the rate of three reactions typically performed in our undergraduate organic chemistry laboratory: a Diels-Alder cycloaddition, a Wittig salt formation, and a Williamson ether synthesis. Ninety-minute refluxes were shortened to 10 min using a laboratory-grade microwave oven. In addition, yields improved for the Wittig…

Although ionic liquids have been investigated as solvents for many applications and are starting to be used in industrial processes, only a few lab experiments are available to introduce students to these materials. Ionic liquids have been discussed in the context of green chemistry, but few investigations have actually assessed the degree of…

We have developed a two-week guided-inquiry laboratory in which first-semester general chemistry students investigate a suspected arson using gas chromatography--mass spectrometry and paper chromatography. In the process of evaluating evidence from the crime scene, students develop and test hypotheses and learn the fundamentals of chromatography,…

The statistical picture of the gender composition of chemistry as reported in national data indicates that women are underrepresented in academe in comparison to their representation in the field as a whole. This article presents data on the perceptions and views of a broad cross-section of women in academic chemistry departments and provides some…

Assigning a popular nonfiction book as a supplemental text in organic chemistry can help students learn valuable skills. An analysis of student feedback on assignments related to a nonfiction book in two different organic courses revealed that students applied the information from the book, improved their communication skills, and were more…

Models play an important role in understanding chemical engineering systems. While differential equation models are taught in standard modeling and control courses, Differential Algebraic Equation (DAE) system models are not usually introduced. These models appear naturally in several chemical engineering problems. In this paper, the introduction…

Diagrams and figures play a central role in science and science education. Research has indicated that, when presented and used properly in a classroom setting, these external representations can contribute to students' understanding of scientific concepts; however, it is apparent that students do not always use, understand, interpret, or value…

Two conventions for preparing dilutions are used in clinical laboratories. The first convention defines an "a:b" dilution as "a" volumes of solution A plus "b" volumes of solution B. The second convention defines an "a:b" dilution as "a" volumes of solution A diluted into a final volume of "b". Use of the incorrect dilution convention could affect…

A hetero-Diels-Alder reaction that proceeds rapidly and only requires a simple filtration to purify the product is presented. The dienophile, 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), is prepared by the heterogeneous oxidation of 4-phenylurazole by the bromenium ion, Br[superscript +], generated in situ by the oxidation of potassium bromide by…

The discovery that galantamine penetrates the blood-brain barrier has led to its clinical use in the treatment of choline-deficiency conditions in the brain, such as Alzheimer's disease. This experiment involves the isolation and structure elucidation of galantamine from "Leucojum aestivum". Isolation of the alkaloid constituents in "L. aestivum"…

Lasers have transformed chemistry and the everyday world. Therefore, it is not surprising that undergraduate chemistry students are frequently exposed to fairly advanced laser techniques. The usual topics studied with lasers are molecular spectroscopy and chemical kinetics. Static and dynamic fluorescence experiments seem to be particularly…

Extending the usefulness of the instruments we have has never been more important. The current economic crisis has prompted all of us to re-examine how money is spent and to try to minimize our expenditures because of future uncertainties. We have been able to breathe new life into an aging 60 MHz NMR spectrometer used by hundreds of…