Two misconceptions about the mechanism of image formation in the human eye are common among students and even in textbooks and other teaching materials. The first attributes all refraction to the eye lens; the second treats the eye as a pinhole camera. To reduce these persistent conceptions of students, a series of simple experiments is presented…

Understanding potentiometry is a difficult task when students in initial courses of Analytical Chemistry are first introduced to instrumental techniques. The closest instrument to them is a pH meter, which is frequently used as a "black box", without a real understanding of how it works. Here we present the assembly of jelly modules that…

Pulsed field gradient nuclear magnetic resonance (NMR) is used to estimate the size of quantum dots (QDs) produced in a simple, fast, small-scale synthesis. This upper-division laboratory experiment teaches the basics of QD synthesis and pulsed field gradient NMR, a powerful technique for measuring diffusion coefficients in solution. The diffusion…

There is an increasing need for fundamental electrochemistry concepts to be taught in the undergraduate curriculum, given the broad applicability of electrochemical technologies in addressing a wide range of global issues from critical energy shortages to real-time medical diagnostics. However, many electrochemical concepts are often taught in…

Demonstration interviews with 27 high school students (18-19 years old) were conducted in Zagreb, Croatia, using several standard experiments on interference and diffraction of light. Students were asked for their predictions, observations, and explanations of the experiments. In this process, many student difficulties were identified, both…

A multistep synthesis of a metal-free organic dye-sensitizer for solar cells was developed as a multifaceted research project for upper-division undergraduate students with a goal of introducing students to the application of organic synthesis in material science, and renewable energy research. The characterization of the dye is done by thin-layer…

In recent years, course-based undergraduate research experiences (CUREs) have been increasing in popularity as replacements for or adjuvants to the traditional laboratory experience. This approach shifts the focus from an exercise-based curriculum to an experiment-based curriculum and provides students with a more authentic and higher-impact…

Thin-layer chromatography, which involves the movement of dyes along a silica-coated plate, is used to observe the progress of chemical reactions and to separate mixtures. We took advantage of this phenomenon to devise a method for generating patterns in the shape of numbers with dots (dot matrix). We prepared the azo dyes necessary for generating…

In this laboratory teaching experiment, commercial cannabis oils were analyzed by undergraduate organic chemistry students using gas chromatography-mass spectrometry (GC-MS) to investigate three isomeric cannabinoids commonly found in cannabis products: cannabidiol (CBD), [delta][superscript 9]-tetrahydrocannabinol ([delta][superscript 9]-THC),…

This manuscript introduces a novel General Chemistry experiment designed to incorporate modern instrumental methods and bioinspired materials in the context of marine environments and sustainability. The experiment explores the influence of collagen on the formation of calcium carbonate (CaCO[subscript 3]) polymorphs over two 2 h lab sessions,…

The topic of chemistry safety was included at the margins of traditional chemistry education in China. In order to understand the concerns of the safety issues based on the new chemistry curriculum in the mainland China secondary school, this study analyzed old and new secondary chemistry curriculum standards via the Natural Language Processing…

A Microsoft Excel workbook has been developed to simplify the quantitative analysis of experimentally measured titration curves for diprotic and triprotic amino acids such as glycine, arginine, histidine, and glutamate. Students perform the titration, enter the data into the worksheet, and manually adjust the resulting pK[subscript a] values to…

Einstein's relation between mass and energy is perhaps the most famous equation of Physics. Despite its simplicity, the meaning of E[subscript 0] = mc[superscript 2] is not easy to grasp. Furthermore, its traditional derivations rely either on the integral of "momentum," on properties of electromagnetic radiation, or even on the…

When the thermal expansion of water is discussed in school or university lessons, functional relationships are often inferred without considering measurement uncertainties. Moreover, in some learning materials, the goal of experimentation and the experimental setup do not match. This creates the wrong picture of scientific practice. In this…

Thermodynamic characterization of micelle formation from an ionic surfactant in aqueous solutions is a classic experiment in physical chemistry. The critical micelle concentration (CMC) and the degree of micelle ionization ([alpha)] can be directly obtained by conductimetry, then thermodynamic parameters ([delta]G[subscript m][superscript o],…