The study of gels and their properties is a compelling topic both technologically and scientifically, and should therefore be emphasized in chemistry and material science syllabuses. In the present laboratory experiment, we propose two experiences, aimed at introducing gelation and gel transport properties using silica gels made from sodium…

The problem of a disc or cylinder initially rolling with slipping on a surface and subsequently transitioning to rolling without slipping is often cited in textbooks. Students struggle to qualitatively understand the difference between kinetic and static frictional forces--i.e., whereas the magnitude of the former is known, that of the latter can…

Chemical kinetics is a branch of physical chemistry that constitutes an essential part of undergraduate education. In general, a complex and expensive experimental apparatus is indispensable for observing the kinetics of a chemical process owing to the continuity of chemical reactions. Thus, intuitive visualization of the chemical kinetics using a…

Safe and high-quality water is essential from both the health and environmental perspectives. Water quality is so important that the United Nations has included water in the 17 Sustainable Development Goals of the 2030 Agenda for Sustainable Development. Thus, the adequate control and treatment of water are necessities. These tasks must be…

In the activity described in this communication, the authors present a simple experiment that can be implemented with moderate operational costs and that allows students to acquire the manipulative skills necessary for chromatographic analysis of a familiar fuel that still plays a fundamental role in providing energy for transport of passengers…

A laboratory experiment utilizing locally available Indian Gooseberry ("Phyllanthus emblica" Linn.) extract as a bioreagent to determine iron(III) is described with the goal of providing students with hands-on experience in spectrophotometry and green chemistry. Spectrophotometry was used to measure the concentration of the complex…

With the enormous reliance on plastics in the world today, bisphenol A, an additive used in the synthesis of many plastics, such as polycarbonate, has been found almost everywhere in our environment including in soil, in natural waters, and inside organisms including humans. A multidisciplinary experiment is presented that involves using flatworms…

Most didactic lab experiments deal with the influence of temperature, concentration, pressure, surface area, and catalysts on chemical kinetics; however, few of them explore the influence of light radiation and the presence of inhibitor agents on reaction rates. In order to investigate the effects of the radiation source and the presence of…

Regioselectivity in hetero Diels-Alder reactions can be observed in a simple reaction between a nonsymmetrical heterodiene and an unsymmetrical heterodienophile. A 9 h and easy to implement laboratory experiment is described, in which students can observe the regioselectivity of inverse "electron-demand" hetero Diels-Alder reactions of…

This is an easy and inexpensive laboratory experiment in which undergraduate students at the Bachelor's degree level in Chemistry can measure formation constants of complexes [Ni(en)[subscript n](OH[subscript 2])[subscript 6-2n]][superscript 2]+ (n = 1, 2 or 3; en = ethylenediamine) through an acid-base titration. The background information…

We present an experiment designed to hone the decision-making skills of (undergraduate) chemistry students by using aqueous crossed aldol reactions. Here, we present two simple crossed aldol reactions based on inexpensive and readily available materials: The condensation of vanillin and cinnamaldehyde with acetone. The procedure uses the variation…

As soon as children can see, they observe that objects fall freely. From a young age, we spontaneously construct interpretative models to understand this everyday phenomenon. Over the last three decades, numerous experiments have been developed to help students understand physics concepts regarding free fall. Although there are many…

Quantum dots (QDs) are considered useful for demonstrating quantum phenomena in undergraduate laboratories due to their monodisperse size and excellent optical properties. Although doping has an increasingly important role in QD fabrication in the semiconductor field, it has rarely been discussed in the context of the undergraduate laboratory. In…

The effect of surfactant adsorption on surface tension, as well as associated thermodynamic concepts are introduced in a laboratory experiment designed for undergraduate students. Using a reliable and accessible method, students measure the surface tension of aqueous solutions at different concentrations of sodium dodecyl sulfate. Students collect…

An undergraduate laboratory experiment for the synthesis of biologically significant bis-4-hydroxycoumarins using a new catalyst is described here. An experimental setup plan, monitoring the reaction by TLC, isolation of the product, safe laboratory handling procedures, and significance of data reproducibility of the result are the main learning…