Vol. 118 No. 2 (2022)

During the last decades, ligands bearing switchable features have emerged as an effective tool to modify the properties of the transition metal complexes upon introduction of a stimulus in the reaction media. In particular, complexes featuring redox-switchable ligands have the ability of changing the Lewis acidity of the complex upon oxidation/reduction, leaving the original steric properties. This feature is particularly interesting because it can be used to modulate the activity of molecular catalysts, and even to shed light into mechanistic aspects of selected catalytic reactions.

Keywords: Organometallic chemistry, homogeneous catalysis, switchable catalyst, redox-reversibility, mechanism

After introducing the meaning of “international years”, it is reported that the UN has proclaimed 2022 as the International Year of Basic Sciences for Sustainable Development (IYBSSD). The aims, which mainly focus on projecting the relevance of basic science in the achievement of the Sustainable Development Goals (SDGs), are discussed, and it is highlighted how the event is an opportunity to promote educational and outreach activities on science in general, and chemistry in particular.

Keywords: international year, IYBSSD, sustainable development

At the beginning of the 19th century, Alessandro Volta presented the first electrochemical cell; Since then, the knowledge of the reactions that generate electric current has not stopped progressing. This article presents the construction of various electrochemical cells using everyday materials. It begins by rebuilding a supposed electrochemical device, the Baghdad battery, dating from the second century BC, and continues with the construction of a portable Daniell battery, a Volta-type battery and a homemade battery using a pencil sharpener and pencil.

Keywords: Galvanic cells, Volta’s cel, electromotive force, redox reaction

As a contribution to the commemoration of the International Year of the Periodic Table (IYPT) 2019, a periodic table designed as a motivating activity for science students is presented. Moreover, several teachers have participated in its creation. It consists of a table in which, linked to the box corresponding to each chemical element, there is a video of a student or a teacher telling the most relevant characteristics of that element. The details of the information exposed, the visual aspect of the table with the faces of the 120 participants and the Internet platform where it is hosted are described.

Keywords: periodic table, International Year of the Periodic Table 2019, videos, chemical elements, QR codes

This article briefly explores the history of tetraethyllead, from its discovery as a gasoline antiknock agent in 1921 until its total world ban. It is examined how, thanks to industrial lobbying, advertising, and lacking independent scientific research, this compound could be so extensively used, despite its extreme toxicity. Also, the alternatives to tetraethyllead available at that time are reviewed, which were well known to the people that promoted its use. Finally, the role of Clair Patterson in drawing attention to the risks of global lead contamination is featured.

Keywords: heavy metal, internal combustion engine, Thomas Midgley , gasoline, global pollution

2022 marks the centennial of the first Solvay Chemistry Conference, which took place from 21 to 27 April 1922 at the Solvay International Institute of Chemistry in Brussels. Its founder, Ernest Solvay, died a month later. In this work, which highlights the two anniversaries, the biography of this well-known Belgian industrialist is summarized, with special emphasis on his extensive relationship with chemistry educators and institutions, and refers to the aforementioned conference, explaining why it was held later than the first physics ones and what it represented for the advance of science.

Keywords: Chemists of the first third of the 20th century, Conseils Solvay, Ernest Solvay, History of Chemistry

It is the 100th anniversary of the Stern Gerlach experiment that demonstrated conclusively the existence of spatial quantization, a key phenomenon in various aspects of Chemistry and Physics, such as NMR and EPR spectroscopies, the maser or the atomic clocks. This historical article describes the motivation for the experiment and the difficulties its authors had to overcome.

Keywords: Stern-Gerlach experiment, space quantization, history of science.