This study proposes three activities for a multidisciplinary laboratory practice with university students of advanced cycles, these didactic activities seek to develop scientific curiosity through the construction of an analytical instrument. To this end, students assemble a microbalance with low-cost frequency meters by replacing the oscilloscope with smartphones, DIY frequency counters, and Arduino development boards, for the educational purpose of illustrating the piezoelectric properties of quartz crystal and its relationship with the resonant frequency by experiential learning.

This study proposes a laboratory practice at the university level that allows active participation and helps understand the concepts of physical-chemical properties and molecular structures with experimentation as a teaching-learning strategy for microscale chemistry. For it, a quartz crystal microbalance is used to detect variations of small amounts of mass. The microbalance is built with low-cost electronic components, an Arduino UNO board, and an OLED screen to determine the evaporation time at room temperature of pure substances and mixtures with different degrees of volatility: Propan-2-ol, ethanol, and water. And with its use, reduce the cost of the chemical reagents used, the amount of waste generated, and reduce the time in the experiments to allow greater participation in the debate and discussion between students and teachers during practice.

The 2022 quarantine period exposed the need to design laboratory instruments that were accessible to students, allowing them to conduct experiments from home. Although many magnetism studies have developed manually displaced gaussmeters, only a few of them have been automated. Therefore, this study presents the design of a gaussmeter made with construction toy parts and an Arduino UNO development board to quantify the magnetic flux density in permanent magnets. To evaluate its operation, precision and robustness tests were carried out. In this way, the Kruskal-Wallis test showed similarity in the experimental readings with the WSH315 sensor between 1.62–3.54 cm. Meanwhile, the Wilcoxon-Mann-Whitney test showed limitations in terms of accuracy. And the Youden-Steiner test showed robustness to polarity rotation in the magnet at a distance of 1.19 cm with the AD22151 sensor. Finally, the ...