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The Journal of Chemical Education announces a call for papers for an upcoming special issue on New Visions for Teaching Chemistry Laboratory.

The principles of process oriented guided inquiry learning (POGIL) are applied to a binary solid–liquid mixtures experiment. Over the course of two learning cycles, students predict, measure, and model the phase diagram of a mixture of fatty acids. The enthalpy of fusion of each fatty acid is determined from the results. This guided inquiry experiment, which was developed as part of the POGIL-PCL (Physical Chemistry Laboratory) Project and tested at multiple institutions, relies on “green” materials and can be carried out by students using simple or sophisticated apparatus.

The POGIL-PCL (Process-Oriented Guided Inquiry Learning in the Physical Chemistry Laboratory) project has developed a series of workshops to introduce faculty to POGIL-PCL and to facilitate the development of new experiments. More than 60 faculty members from various institutions have attended these workshops. Workshop participants were surveyed in order to evaluate the effectiveness of the workshop and better understand why faculty choose to adopt POGIL-PCL. Of the participants who completed the survey, 77% had used POGIL-PCL experiments. The results of the survey show that personal influence is a major factor in all stages of the adoption process.

The POGIL-PCL project implements the principles of process-oriented, guided-inquiry learning (POGIL) in order to improve student learning in the physical chemistry laboratory (PCL) course. The inquiry-based physical chemistry experiments being developed emphasize modeling of chemical phenomena. In each experiment, students work through at least two learning cycles in which they make predictions, collect data, model the data, and discuss its meaning. The design of the student laboratory experiences resembles the apprenticeship model of research because students carry out an experiment with faculty guidance to determine which parameters are best modified in subsequent trials of the same experiment. The POGIL-PCL model is illustrated using the example: “What are the kinetic parameters of a heterogeneous reaction?” Typical student results and responses are discussed.

A rationale for the removal of the hybrid atomic orbital from the chemistry curriculum is examined. Although the hybrid atomic orbital model does not accurately predict spectroscopic energies, many chemical educators continue to use and teach the model despite the confusion it can cause for students. Three arguments for retaining the model in the chemical curriculum are presented. These arguments are then refuted and methods for teaching chemistry without invoking the hybrid atomic orbital model are presented to show how the model can be removed from the chemistry curriculum with little negative effect.

The Physical Chemistry On-Line (PCOL) consortium has developed and conducted a series of short-term projects for use in the physical chemistry curriculum. The projects involve faculty and students from geographically dispersed institutions, are short in duration (~4–6 weeks), and use email and the World Wide Web for communication and information distribution. They are designed to enhance physical chemistry at colleges and universities that may have limited resources available for physical chemistry by offering an alternate pedagogical approach. This paper will highlight the motivations of the participants, outline the specific projects used to date, and provide some evaluation of the pedagogical effectiveness of the approach.

The collision induced dissociation (CID) of small gas phase platinum and platinum carbonyl cluster anions, Ptm− and Ptm(CO)n− (m=3−6), has been studied using a guided ion beam tandem mass spectrometer. The threshold energies obtained from analysis of the CID cross sections for carbonyl and metal atom loss are equated with binding energies. The binding energies of CO to the platinum cluster anions are indicative of two different binding sites, terminal (about 80–110 kJ/mol) and bridged (220–250 kJ/mol). Energies required to removed platinum atoms from the bare cluster anions are 410–470 kJ/mol, a substantial fraction of the bulk enthalpy of vaporization, 570 kJ/mol. Using threshold energies for both primary and secondary CID products in thermodynamic cycles, we have determined thermochemical stabilities of additional neutral and anionic platinum carbonyl species.

This letter is in response to those who do not wish to retire the hybrid atomic orbital model. The argument is made that students in general and organic chemistry lack the necessary background skills to properly understand orbital bonding models, and thus, teaching these models in these courses leads many students to generate misconceptions.

The NMR Collaborative Training Partnership is an NSF sponsored project that provides several nearby two-year and four-year institutions access to a 300-MHz FT-NMR. Using Web-based materials we teach students who do not have direct access to an instrument the basics of how an NMR spectrum is generated. We also have a Web server and remote software that allows students to generate real spectra from samples they have submitted to their instructor. In this way, students who do not have a local FT-NMR can gain experience with this important technique.

A number of modifications to the standard keto–enol experiment in the physical chemistry laboratory are suggested for using modern NMR instruments now available in many chemistry departments. These modifications include sample preparation using a deuterated solvent for FT–NMR frequency locking, in-depth analysis of a proton spectrum acquired with a medium field (~300 MHz) NMR, examination of the temperature dependence of equilibrium processes, and multinuclear investigations. Remote access to the instrument and subsequent data analysis facilitated by the Internet are discussed. These methods permit students to learn about a wide variety of concepts within an integrated single-experiment design. We include student data in our analysis and an overview of possible extensions to the experiment.

The formation of Lewis acid-base adducts of the organotin trihalides, CH 3 SnCl 3 , C 4 H 9 SnCl 3 , and C 6 H 5 SnCl 3 , with acetonitrile, DMA, triphenylphosphine oxide (TPPO), and triethylphosphine oxide (TEPO) were studied by calorimetry and NMR spectroscopy. Schematic mapping of the calorimetry results for the TPPO adducts in benzene showed that the data are best fit by the assumption of simultaneous formation of 1 1 and 1 2 adducts. For the C 6 H 5 SnCl 3 -TPPO system K 1 = 4.3 X 10 4 , K 2 = 55, Δ H 1 = −13.3 kcal/mol, and Δ H 2 = −10.8 kcal/mol. These equilibrium constants correspond to 93% 1 1 adduct and 1 2 adduct at equilibrium after the acid and base are mixed in equimolar (0.1 M ) concentrations. Thus, for this system and all others studied the 1 1 adduct predominates. Equilibrium constants for the formation of the 1 1 adducts were determined by 119 Sn or 31 P NMR spectroscopy from the shifts obtained in a series of equimolar mixtures of acid and base. These constants vary from approximately 1 for the acetonitile adducts to greater than 10 5 for TEPO and reveal the expected basicity order TEPO > TPPO > DMA > acetonitile.