In this article we present a simple technique for determination of the Young modulus of the material of a metallic ruler using it as a cantilever. This method employs with a slide potentiometer and a digital multimeter. The linear region of potentiometer resistance which is calibrated in terms of length has been used to record the load vs.…

The refractive index of a liquid is known to depend strongly on the temperature gradient of liquids. When a laser beam passes through a transparent material going through thermal diffusion, the light projected onto a screen will be displaced in relation to the thermal diffusivity. A simple apparatus is used to measure the time evolution t of the…

Granular flows appear frequently in the natural world and in civil engineering applications. These flows can exhibit features which are surprising and counter-intuitive and are often used to test the limits of the classical continuum approximation for modelling of fluid flows. An important sub-class of the granular flows are the gravity-driven…

Teaching the noncommutativity of the product of matrices to high school or college level students is a difficult task when approached from a purely formal perspective. The aim of this paper is to present a simple experimental activity for teaching the noncommutativity of the matrix product, based on the Jones calculus, a mathematical formalism for…

We present an experiment designed to study standing waves in a tube with one closed end. Two smartphones are used, one to emit a sound signal with a chosen frequency and another equipped with a microphone to detect the sound pressure level inside the tube. Due to the finite diameter of the tube, the standing wave node (or antinode) appears…

We describe a project implemented in the honors section of an upper-level analytical chemistry undergraduate course, in which students designed an experiment to compare the performance of two analytical techniques to determine the amount of ascorbic acid in a commercial sample. This project designed for 18 students is composed of three stages. In…

Proteins are "magical" workers inside our body, as they accomplish most of the cellular functions. Here we report on a novel approach to teach protein folding and unfolding, using magnets and flexible 3D-printed protein structures. To illustrate this physical process, we used colored circular magnets designed for whiteboards, connected…

Old physics textbooks give us a great opportunity to learn about the history of science and rediscover different methods to teach physics to our students. There are many disused and forgotten experiments in them, but these can still be very useful to affirm and understand physics. This is the case of an instrument used in the 19th century to…

[This paper is part of the Focused Collection on Instructional labs: Improving traditions and new directions.] In this paper, we describe the results of a research project whose goals were to (1) develop and implement video-based experimental investigations using the Investigative Science Learning Environment (ISLE) approach and (2) study how…

Each student's individual experience in learning is very important. Lower secondary school students are engaged in activities that focus on inquiry rather than the acquisition of scientific knowledge in science classrooms. Therefore, the experiences and thoughts of lower secondary school students in the stage of scientific inquiry need to be…

Virtual experiments offer opportunities for students to engage in the scientific process and observe scientific phenomena. However, virtual experiments are not always effective for learning. The current study examined how two small manipulations might support better learning from virtual experiments and the extent to which this varied across…

This report describes a laboratory experiment for an undergraduate-level inorganic chemistry or biochemistry course involving the study of the kinetics of the catecholase activity of a synthetic nickel­(II)-oximate complex. A model substrate, 3,5-di-tert-butylcatechol(DBC), undergoes aerobic oxidation to 3,5-di-tert-butylbenzoquinone (DBQ) in the…

Poinsettia ("Euphorbia pulcherrima") contains anthocyanins that dissolve in water and exhibit color changes due to changing pH. This property makes the poinsettia extract a useful acid-base indicator for pH demonstrations. When combined with common household materials, this experiment can be used as an alternative low-cost tool in…

MóviLab (Moving Lab) was an educational strategy developed at Universidad Industrial de Santander, Colombia, to promote chemistry and science among schoolchildren and teenagers from far rural areas of the Santurbán moor in Colombia during the COVID-19 pandemic. The strategy consisted of designing a kit with chemistry experiments that could be done…

Herein, two simulated electrochemistry experiments, namely, the (i) electrochemical series, using an electronic half-cell module, and (ii) citrus fruit battery series are demonstrated for undergraduate chemistry students. The demonstration can be performed for in-person and remote students by connecting the electronic half-cell module to a…