Chemical equilibrium is one of the most important concepts in chemistry. The changes in properties of the chemical system at equilibrium induced by variations in pressure, volume, temperature, and concentration are always included in classroom teaching and discussions. This work introduces a novel, geometrical approach to understanding the…

This paper describes a laboratory exercise used to address the ongoing need for nanotechnology-related, hands-on laboratory experiences for undergraduate students. Determination of the electrochemical behavior of student-fabricated silver nanogrids is reported. Students successfully used cyclic voltammetry to analyze silver nanogrids printed using…

A procedure for the study of structural differences and intermolecular attraction between ethanol and 1-butanol based in laboratory work is described. This study provides comparisons of data retrieved from both a determination of boiling point and gas chromatography traces for the mixture. The methodology reported here should provide instructors…

This work seeks to elucidate undergraduate science students' basic knowledge of concepts related to the energy changes for a simple heating curve and their ability to integrate related concepts. The participants were drawn from first and second semester General Chemistry classes, as well as junior/senior level Physical Chemistry classes at a…

All living structures, from archaea to human, are open thermodynamic systems analysed through nonequilibrium thermodynamics. Nonequilibrium thermodynamics is a field with important applications to life sciences, which is very often left out of life science courses. A three-step method is suggested to make an easy introduction of nonequilibrium…

The scope this article was to develop an instrument to measure Chemistry students' ability regarding 'physical bonding' and to validate it. A number of 24 items were developed by mapping items to cognitive levels described by the Marzano taxonomy. A number of N=73 students were evaluated. Four items exhibited a MNSQ >1.3 and were eliminated…

This paper describes a professional development model for developing science teacher leaders that has evolved and been refined through working with 16 high school chemistry and physics teachers in high-needs schools over the past 3 years. The theoretical framework draws upon Goodwin's notion of professional vision and Dempsey's four metaphors to…

In this paper, we report an experiment intended as a tool to introduce chemistry and materials science students to several chemical concepts through the determination of the best experimental conditions for the formation of calcium oxide (lime) from a source of high content of calcium carbonate (eggshells). Thermal gravimetric analysis (TGA),…

We report here a method that utilizes the vapor pressure of HCl(g) above a concentrated HCl(aq) solution as an extremely simple and safe method to produce small amounts of HCl vapor in an IR gas cell. This vapor pressure approach can also be used to produce DCl(g) by introducing a few drops of concentrated DCl(aq) into the gas cell.

Adsorption of methylene blue and malachite green was carried out using "Luffa cylindrica" sponges as adsorbing material. We provide a very illustrative exercise about the use of common natural materials requiring little preparation to solve environmental tasks in a routine laboratory situation such as using dyes. In addition, the…

To inspire upper-division undergraduate students to gain a deeper understanding of biorefinery, an experiment related to biofuels and lignin-based sunscreen products from corncob was performed in multiple offerings of a summer-semester class. Specifically, corncobs were pretreated with 1% H[subscript 2]SO[subscript 4] to obtain hemicellulose…

It is essential that chemists develop strong oral communication skills. At the undergraduate level, this requires students to build confidence in their ability to speak without a script and to utilize graphics effectively. We have developed a short activity that helps address common presentation issues such as overuse of text and reading verbatim…

A new laboratory experiment investigating the ternary phase equilibrium of water-propan-2-ol-sodium chloride with one-, two-, and three-phase regions has been developed. Observations of the type and number of phases of a series of mixtures of the three components were made, and the results are then used in a systematic way to more finely choose…

An experiment involving a moisture-sensitive synthesis and spectroscopic characterization suitable for the advanced inorganic laboratory course is presented. The acid-base complex ammonia borane (AB) is synthesized from the heterogeneous reaction between sodium borohydride and finely ground ammonium sulfate in tetrahydrofuran solvent. AB is…

The different reactivities between 1°, 2°, and 3° butyl chlorides by the unimolecular nucleophilic substitution (S[subscript N]1) mechanism were easily observed at 60 °C by a solvolysis reaction in ethanol with ether formation. The hydrogen ion from the byproduct HCl reacted with an acid--base indicator such as methyl red to induce a color change.…