Scanning electron microscopy (SEM) was introduced into undergraduate physical chemistry laboratory curriculum to help students observe the phase composition and morphology characteristics of tin–lead alloys and thus further their understanding of binary alloy phase diagrams. The students were captivated by this visual analysis method, which allowed them to more fully consider the relationship between macroscopic behaviors and microscopic structures of materials. During this process, the abilities of critical thinking were inspired, and a spirit of team work came into being.

The determination of the solid–liquid phase diagram of a binary system is always used as an experiment in the undergraduate physical chemistry laboratory courses. However, most phase diagrams investigated in the lab are simple eutectic ones, despite the fact that complex binary solid–liquid phase diagrams are more common. In this article, the cooling curves of phenol–t-butanol mixtures are measured and the phase diagram of this system is found to give three eutectic points and two congruent melting points. The laboratory provides the students a practical way to investigate a complex system with their own efforts and teamwork spirit.Keywords: Alcohols; Collaborative/Cooperative Learning; Hands-On Learning/Manipulatives; Laboratory Instruction; Phases/Phase Transitions/Diagrams; Phenols; Physical Chemistry; Thermal Analysis; Thermodynamics; Upper-Division Undergraduate;

The poly-glutamic acid modified electrode has been prepared by direct electro-polymerization of D-glutamic acid on the surface of glassy carbon electrode. In pH 4.2, 0.1 mol L−1 HAc-NaAc buffer solution, the film modified electrode exhibited remarkable enhancement effect to the electrochemical responses of ferulic acid. The action mechanism was preliminarily explored. In the range of 2.0 × 10−7 to 1.0 × 10−5 mol L−1, and 1.0 × 10−5 to 3.0 × 10−4 mol L−1, the oxidation peak current has a linear relationship to the concentration, and the detection limit was estimated to be 7.0 × 10−8 mol L−1. This method has been adopted to detect trace amount of ferulic acid in Chinese proprietary medicine, and the recovery was from 97.8 to 102.4%.

In pH 5.0, 0.1 mol l−1 NaAc-HAc buffer solution, 2,4-dinitrophenol and 2,5-dinitrophenol exhibited sensitive and distinguishable voltammetric responses at the glassy carbon electrode modified with poly-aspartic acid. By measuring the reduction peak currents of nitro groups in different positions, dinitrophenol isomers have been determined simultaneously and quantitatively. The linear calibration ranges were 1.1 × 10−6–6.0 × 10−4 mol l−1 for 2,4-dinitrophenol and 7.0 × 10−7–6.0 × 10−4 mol l−1 for 2,5-dinitrophenol, with detection limits of 2.7 × 10−7 and 1.1 × 10−7 mol l-1 respectively. This method has been applied to the detection of dinitrophenols in simulation water sample, and the recovery was from 96.7 to 102.5%.