An upper-division undergraduate- or graduate-level laboratory experiment, challenging students to identify bovine serum albumin, equine myoglobin, bovine calmodulin, and bovine cytochrome c, uses four methods of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS): linear positive, in-source decay, peptide…

The Leidenfrost nanochemistry synthesis of gold colloids was introduced in this "Journal" as an advanced method to synthesize gold nanoparticles during an undergraduate nanochemistry research project. When trying to repeat these experiments in the laboratory, we experienced difficulties in the synthesis of the gold nanoparticles since…

In a classical electronic laboratory, there is an experiment where a diode is connected in a series with a resistor and a variable DC voltage source in order to draw the characteristic I-V curve of the diode. Input voltage is gradually increased starting from 0 V, and the potential difference between the diode's terminals is read by using a…

BYOL (Bring Your Own Lime), a novel laboratory experiment, is introduced in this paper. Students are encouraged to bring affordable household and grocery store chemicals into the classroom. The Bring Your Own Chemical (BYOC) concept demonstrates to students that food and household products are chemicals too. Citruses are often used to highlight…

In this paper, we show a laboratory experience describing the possibility to build a sensor using a coil to measure small thicknesses of materials with the possibility of measuring temperature simultaneously, with the same built sensor. Its operation is based on the following facts: An electric current (a.c), flows through a coil and a magnetic…

We report on a simple, rapid, and room-temperature undergraduate-level experiment for gold nanoparticle synthesis, analysis, and utilization as a catalyst for the sodium-borohydride-assisted reduction of methylene blue and Congo red dyes. Typical procedures toward gold nanoparticle formation require an elaborate, lengthy synthesis (some requiring…

The concept of equilibrium vapor pressure plays a key role in the general chemistry curriculum; it is among the first and most easily demonstrated examples of equilibrium and frequently caps off the first semester of general chemistry where it illustrates the properties of liquids and intermolecular forces. We report here simple modifications of…

All-solid-state polymer electrolytes (SPEs) have been regarded as an advisible alternative for simultaneously overcoming the safety issues and high energy density demands presented in traditional lithium batteries, and they represent the development orientation of energy storage devices. This course describes the preparation of a cross-linked and…

Secondary metabolite compounds contained in each plant genus have certain characteristics, which is true also of the flavonoid in the genus "Artocarpus." In the experiment described here, third-year undergraduate students performed the isolation and characterization of cycloartocarpin from the roots of "Artocarpus altilis"…

According to the definition, surface tension could be affected not only by intermolecular interaction but also by molecular area. However, in chemistry textbooks, surface tension is mainly explained only in terms of intermolecular interaction. Although the existing surface tension concept in the textbooks can lead to a variety of counterexamples,…

A classic undergraduate introductory experiment is to measure the diffraction and interference pattern from single and double slits to determine slit width and separation. Studies show that Course-based Undergraduate Research Experiences (CUREs) can make science more inclusive when offered at the undergraduate level. Additionally, CUREs help…

A laboratory exercise for the synthesis of a sulfonated styrene-"co"-maleic anhydride polymer and its application as a stain blocker on nylon-6,10, is described. The effectiveness of the sulfonated polymer to prevent the conjugate base of an acid dye from staining the polyamide is demonstrated. This experiment is designed for…

To study the absorption of ultrasound in plexiglas we propose to use gadgets that are available to each student: an ultrasound humidifier, a liquid crystal display of a pad, a polaroid analyzer, a digital camera, a multimeter with thermocouple, and a stopwatch. These devices allow us to visualize a region in plexiglas where ultrasound is absorbed…

Although teaching laboratories offer students the opportunity to act and think like chemists, in many cases students simply follow written procedures to generate predetermined outcomes. In recent years, there has been a movement toward inquiry-, problem-, and discovery-based learning. In a similar vein, the first-semester introductory organic…

Newton's law of cooling describes an object whose temperature decreases exponentially with time. Because of its many applications, it is a frequent topic of introductory physics labs. In this article, I describe an experiment designed for the freshman year algebra-based physics course that applies this law to answering the question, "Why…