Modifications are presented for the iodine clock reaction to introduce the concept of activity and to help students better appreciate molecular aspects of chemical equilibrium. The addition of an unreactive salt affects the activity of the reactants in the iodine clock reaction. The difference in activity affects how long the iodine clock reaction…

A chemistry laboratory experiment is described to introduce undergraduate college students to membrane separation technology. This experiment combines a simple nanowire membrane fabrication and visually indicated molecule separation. The membrane is produced via coprecipitation synthesis followed by a filtration assembly process, which can be…

A mixture of salt water and isopropyl alcohol is immiscible, forming two separate liquids with the organic layer on top and aqueous layer on bottom. When universal indicator is added to such a mixture, all of the indicator compounds in the universal indicator preferentially dissolve in the alcohol--except for phenolphthalein at high pH. Mixtures…

The yellow-blue color pair has been used in creative artwork such as paintings and designs and in color engineering. Herein we present a method for using the yellow-blue combination in a chemistry lesson dealing with [pi]-conjugated molecules for first-year undergraduate students who are not science majors. The lesson begins with an introduction…

3D printers have facilitated a wealth of 3D printed molecular models illustrating key structural concepts for student learning. However, general adoption of 3D printed models in the organic chemistry classroom proceeds slowly as the majority of consumer-grade 3D (fused deposition modeling (FDM) and resin) printers are inherently monochromatic,…

This article describes a simple way to introduce nanomaterials using the presence of carbon nanodots (CNDs) in widely available food. Budweiser® beer and Coca-Cola®, commercial foods that are commonly accessible, were utilized to demonstrate the optical property of nanoparticles. Specifically, green and violet laser pointers were employed for the…

In contrast to a macroscopic solid, the color and spectroscopic properties of gold nanoparticles change with size. Here, we propose a teaching platform for high school students (hereafter defined as students, attending secondary school in Europe, preparatory high schools in the US, or any educational institution of a comparable level) that…

Recently, researchers have paid extensive attention to colorimetric/fluorimetric probe development and its applications in biological and industrial samples. The actual development of such probe molecules, however, often requires an iterative process to achieve certain goals such as selectivity and sensitivity toward a target analyte. In spite of…

Anthocyanins are natural pigments belonging to the flavonoid family that generate the red, blue, and purple colors of fruits, vegetables, and flowers. Their structure and color are dependent on various factors, like the pH. Anthocyanins appear red in acidic, purple in neutral, and blue in basic solutions, making them suitable for use as natural pH…

A new undergraduate inorganic chemistry laboratory experiment is presented. An introduction of the spectrochemical series and ligand exchange is explored using the coordination complex dirhodium tetraacetate, Rh[subscript 2](OAc)[subscript 4]. Students have measured the absorption spectra of the Rh[subscript 2] complex in the presence of various…

Surface structures on the nanometer size scale can impart new and exciting properties to bulk materials. Nanoscopic structures on hydrophobic materials can result in superhydrophobicity and structural coloration. We present an interdisciplinary experiment that introduces undergraduate students to nanotechnology by manipulating the…

Flotation as a method of separation is widely researched and is applied in many industries. It has been used to address a wide range of environmental issues including treatment of wastewater, recovery of heavy metals for recycling, extraction of minerals in mining, and so forth. This laboratory attempts to show how such a simple method can be used…

A laboratory experiment is described that extracts the tetrapyrrolic teal-colored biliverdin IXa, as its dimethyl ester, from commercially available emu eggshells. The extraction of ~10 mg samples of biliverdin is simple and requires two 3 h lab periods: A two-step acid digestion and liquid-liquid extraction, followed by short silica gel flash…

A laboratory experiment is described in which students measure the amount of cetirizine in allergy-treatment tablets based on molecular recognition. The basis of recognition is competition of cetirizine with phenolphthalein to form an inclusion complex with ß-cyclodextrin. Phenolphthalein is pinkish under basic condition, whereas it's complex form…

Frederick Sanger's early work on protein sequencing through the use of colorimetric labeling combined with liquid chromatography involves an important nucleophilic aromatic substitution (S[subscript N]Ar) reaction in which the N-terminus of a protein is tagged with Sanger's reagent. Understanding the inherent differences between this S[subscript…