This laboratory investigation challenges students to synthesize, analyze, and compare viable alternative fuels to Diesel No. 2 using a renewable resource, as well as readily available reagents and supplies. During the experiment, students synthesized biodiesel from soybean oil in an average percent yield of 83.8 ± 6.3%. They then prepared fuel samples consisting of commercial Diesel No. 2, B100 (100% biodiesel), and blended B20 (80:20 Diesel No. 2 to biodiesel). During analysis, the students determined that the fuels contained an average energy value of 3626.2 ± 622.0 kJ/kg (B100), 3675.6 ± 723.7 kJ/kg (B20), and 4349.5 ± 1019.2 kJ/kg (Diesel No. 2). The experiment requires three 50 min lab periods and reinforces crosscutting educational science standards. It can enrich science discussions in either a high school or an introductory university chemistry class regarding sustainability and stewardship.

This laboratory experiment challenges students to identify the country of origin of raw coffee beans from around the world by calculating the percent caffeine and percent water in the supplied samples. The implementation of this experiment enables students in introductory chemistry classes to gain greater understanding of the chemical analysis process and the Beer−Lambert law. Using commercially available raw (green) coffee samples, students extract caffeine from the grounds as an aqueous solution and determine the percent caffeine using UV− vis spectrophotometry. In a second portion of the experiment, raw beans are roasted to determine the percent water content. Using both pieces of data, students are asked to identify the country of origin of given coffee samples in which the percent caffeine ranged from 1.14 to 1.80% (w/w) and the percent water loss ranged from 3.27 to 10.8% (w/w).

This case study demonstrates the ability of high school chemistry students, with varying levels of math preparation, to experience learning-gains on state and district assessments as it relates to chemical reactions, thermodynamics, and kinetics. These advances were predicated on the use of a teaching style rooted in abstract reasoning. The methodology was presented to students and modeled by the instructor over an entire school year to reinforce key proportional relationships featured in the balanced chemical equation and related topics such as acids and bases, reaction rates, equilibrium, and conservation of matter. Despite the small sample size, there was a general increase in student success, indicated by a statistically significant difference between students receiving instruction rooted in concrete reasoning and students receiving instruction rich in abstract reasoning.

S y n t h e s i s o f a C a n d i d a t e a -H u m a n T h r o m b i n I r r e v e r s i b l e I n h i b i t o rAbstract: a-Human thrombin is a potent platelet agonist involved in the blood coagulation cascade and is an attractive target for an anticoagulant agent due to its involvement in several debilitating diseases. In this contribution we present attempts to develop a new architecture for size-selective serine protease inhibitors that utilize a fully methylated icosahedral p-carborane as a dominating hydrophobic pharmacophore. Using a computational docking program, flexX, a carborane-containing inhibitor was designed and synthesized. Computationally, this compound displayed the ability to provide ligand-protein binding interactions throughout the thrombin's main active site (S1-S3), while positioning an acylating group for facile irreversible attack at the Ser 195 hydroxyl group.