The goal of this study is to present and evaluate a different way of teaching concepts related to the reflection of light (incident beam, reflecting beam, angle of incidence, angle of reflection, surface, regular reflection, and diffuse reflection). The participants were 42 sixth-grade students (between the ages of 11 and 12) attending a public…

Students come to class with little understanding about torque, angular velocity, and angular acceleration despite the fact that these physical science concepts are frequently observed. For example, torque occurs when car and bicycle tires rotate, the movement of fishing pole when hooking a fish, and when a person uses a hammer to drive in a nail.…

Electrochemistry is primarily taught in first-year undergraduate courses through batteries; this lab focuses instead on corrosion to apply electrochemical concepts of electrolytes, standard reduction potentials, galvanic cells, and other chemistry concepts including Le Chatelier's Principle and Henry's Law. Students investigate galvanic corrosion…

This paper presents a system for remote monitoring of turbidity data that can detect light intensity and temperature using a microcontroller and the Internet of Things. The system comprises a light dependent resistor and infrared temperature sensor interfaced with an ESP-12E microcontroller, a programmable data acquisition platform; together these…

Quantum dots (QDs) are useful for demonstrating the particle-in-a-box (PIB) model utilized in quantum chemistry, and can readily be applied to a discussion of both thermodynamics and kinetics in an undergraduate laboratory setting. Modifications of existing synthetic procedures were used to create QDs of different sizes and compositions (CdS…

The purpose of this paper is to present and discuss an alternative solution to an experimental problem given to high school students in the XXII Ibero-American Physics Olympiad held by Colombia this year. From the measurements of electric current and potential difference across a small tungsten filament lamp students should find the dimensions of…

This experiment prepares a large (M[subscript r]: 1821 g mol[superscript -1]) triple helicate complex quickly in one pot from inexpensive starting materials. The protocol illustrates the power of self-assembly in a simple manner that is suitable for second-year general chemistry students using reversible imine bond and metal-ligand bond formation.…

An introductory general chemistry laboratory course was developed to provide an authentic research experience in environmental chemistry. First- and second-year students learned general chemistry concepts and laboratory skills in the context of snow chemistry while participating in the course-based undergraduate research experience. Students were…

Designing and conducting sound and informative experiments is an important aspect of inquiry learning. Students, however, often design experiments that do not allow them to reach conclusions. Considering the difficulties students experience with the process of designing experiments, additional guidance in the form of an Experiment Design Tool…

In this laboratory experiment, students performed thermogravimetric analysis (TGA) coupled with mass spectrometry (MS) of herbaceous materials (TGA-MS) and learned to analyze mass-loss curves, as well as identify common fragmentation ions. The experiment is the first one to present the application of TGA in a currently relevant topic: biomass…

Laboratory reports written in the style of a standard scientific article are commonly used to assess student learning in biochemistry laboratory courses. While most students can complete the Materials and Methods or Results sections successfully, many have difficulty with the Introduction and Discussion. They fail to place their data in a larger…

The ability of certain organometallic reagents to react via 1,2- or 1,4-addition to an a,ß-unsaturated ketone is a fundamental example of regioselectivity at the second-year undergraduate organic level. The following two experiments were designed to demonstrate this preference by exploiting carvone as an inexpensive chiral, nonracemic substrate.…

An undergraduate experiment for the organic laboratory is described that utilizes microwave heating to prepare 5- substituted 1H-tetrazole derivatives through a (3 + 2) cycloaddition between aryl nitriles and sodium azide. The reaction mixture is analyzed by thin layer chromatography. The products are purified through an acid-base extraction and…

This paper describes an undergraduate laboratory experiment where students study the heating behavior of magnetic nanoparticles in the presence of alternating magnetic fields. Average score on the post-test was 45±12% for students who completed the lab online, versus 43±11% for those doing the activity hands-on. Post-test scores were significantly…

Lab-based learning is an essential part of any undergraduate chemistry curriculum as it incorporates necessary and required hands-on experiential learning. However, in response to the COVID-19 pandemic, many students are learning from home, rendering laboratory instruction a particular challenge. Options for educators include third party virtual…