A laboratory experiment was designed to provide students with an introduction to byproduct valorization by producing an analogue of biodiesel (fatty acid ethyl esters, FAEE) via lipid extraction and subsequent transesterification from spent coffee grounds (SCG). Valorization is the process of upgrading underutilized or discarded wastes or…

Potash, an essential raw material of the 18th century, used to be produced from the ashes of plants. Known since antiquity, it was in 1807 that Humphry Davy put an end to the decades-long controversy about its nature as a compound. The technology behind potash production was implemented in Brazil by the Portuguese naturalist Frei Velloso. The…

This laboratory experiment consists of the synthesis of two series of alkaline-earth titanates (calcium-strontium and strontium-barium)to corroborate Vegard's law by obtaining their X-ray diffraction patterns and plotting the lattice parameter versus mole fraction of both cations. This experiment allows students to understand the key concepts in…

A [beta]-lactam, the core structure unit of clinically important antibiotics such as penicillin and cephalosporin, is one of the most commonly encountered four-membered heterocycles in organic chemistry and is widely used in medicine and biochemistry. The Kinugasa reaction, a copper­(I)-catalyzed cycloaddition of a terminal alkyne with a nitrone,…

An experimental design by combining hydrogel and ethylenediaminetetraacetic acid disodium salt (EDTA) for visually displaying chemical complexation reactions is developed. The Na[superscript +] ions on the [alpha]-l-guluronic acid (G) unit of the sodium alginate molecule undergo an ion exchange with a divalent cation, so that the G units are…

We describe an experiment in which students use research-grade instrumentation to collect gas adsorption data in triplicate in a single 3 h laboratory period. The experiment reinforces the thermodynamic concepts taught in upper level physical chemistry courses and hands-on experience with instrumentation used in research laboratories. The speed of…

This article describes an enrichment and extension of a published applied chemistry experiment involving the use of distilled fragrant compounds of natural plants to prepare facial toner. The original protocol failed to consider quality evaluation of the self-prepared facial toner. Herein, an additional experimental section is included for…

Polymer chemistry lab experiments present a unique opportunity to allow students to experience the consequences of reaction mechanisms on the properties of the resulting product. In this organic chemistry experiment, students prepared a polyamide by three different reaction mechanisms that represent step-growth and chain-growth methods of…

In this paper, we present a demonstration of Ohm's law on a spreadsheet. Students can perform an experiment of Ohm's law like they perform in laboratories. The only difference is that the apparatus is virtual. The students record readings of current through the circuit and potential difference across a resistor. A graph is drawn between I and V to…

The reduction of alkenes usually involves a hydrogen source and a catalyst. This process is both expensive and not well-suited for a large teaching laboratory. This paper presents an alternative procedure using a mixture of cobalt chloride and sodium borohydride to achieve the reduction of methyl oleate to methyl stearate. This procedure is safe,…

We herein report an efficient aerobic oxidative cleavage of meso-hydrobenzoin to benzaldehyde using a heterogeneous earth-abundant metal oxide catalyst. The reaction can be carried out at 70 °C in ethanol and uses a balloon filled with O2 as oxidant. Reagents are simple and have long shelf lives, and the whole laboratory exercise can be done in…

The bioinspired polymer polydopamine is synthesized and deposited on semiconductive glass substrates under different synthesis conditions (pH and oxidant type). Electrochemical methods are used to verify polymer deposition on the substrate and to examine the charge transfer properties of the obtained coatings. The presence of aromatic rings from…

We have designed an Arduino-based experiment to check the linear relationship between charge and voltage drop in a capacitor. The electric charge stored in a capacitor is determined by the numerical integration over time of the electric current during the charging or discharging processes through a resistor. Instead of using scientific software to…

The prompt introduction of single-molecule science into undergraduates' curricula is an urgent but challenging task. However, the research experiments are often too complicated and the instruments are too expensive to be widely transferred into a compulsory course of undergraduate students. Herein, we introduce a recently developed nanopore…

Electroscopes have been widely used in physics education for several reasons, such as their simplicity, sensitivity and visual appeal, showing macroscopic phenomena related to the microscopic world. Although they are capable of highly accurate measurements, the procedures involved in these measurements encounter some obstacles when performed with…