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The inclusion of achievements in science awarded with the Nobel prize in chemistry can give students in chemistry lessons inspiring and, above all, motivating insights into current researches. The awarded researches give an important basis for the conception of experimental teaching courses and are fundamental for the design of chemistry lessons according to the principle of scientific accuracy and topicality. Based on Benjamin List′s work, the following article presents an experimental and theoretical approach to asymmetric organocatalysis for pupils in accordance with the principle of exemplary teaching. Due to the low hazard potential of the reactants and products as well as the simplicity of the procedure, pupils can carry out the experiment and derive the reaction mechanisms using their technical competences acquired during their school career and thus they can understand the basic concepts of asymmetric organocatalysis. In addition, classical reactions to detect functional groups of organic molecules and analyses for the characterisation of the products are used, which, in comparison with the base‐catalysed aldol reaction, allow access to the concept of enantioselectivity. The comparison of the base‐catalyzed with the L‐Proline‐catalyzed aldol reaction enables the discussion of ecological and economic aspects of both reaction methods and promotes communication and evaluation skills as well as reflection in scientific contexts. [ABSTRACT FROM AUTHOR]

A new method for a quantitative analysis of glucose is presented. For this purpose, photometric recording of the oxidation of glucose in a weakly alkaline solution of iodine, potassium iodide and starch is used. The oxidation of D‐glucose lowers the concentration of the blue polyiodide‐amylose‐complex, what can be detected photometrically. Using pseudo‐first‐order reaction conditions the reaction rate is found to be proportional to the absorption of the solution. The pseudo‐first‐order rate constant, k', is proportional to c0(glucose). Thus, an unknown glucose concentration can be determined by its rate constant k'. The analysis of the experimental data requires basic knowledge in reaction kinetics. The reactions that proceed within the solution can be used for exercises in chemical equilibria and redox reactions. Hence, the method can be introduced in upper secondary chemistry classes. It can be applied in order to analyze different soft drinks and juices. Furthermore, it is suited to implement digital media into chemistry lessons. The photometer can be replaced by a smartphone on which a suitable app is installed. The app allows a time‐resolved measurement of the color‐depth of the solution by recording RGB‐data. The construction of a respective "photometer cell" is described. The results obtained with the smartphone are in very good accordance with those form the photometer. [ABSTRACT FROM AUTHOR]

In experimental courses, the experiment of the oscillating deflagration of a methanol‐air mixture on a copper or platinum wire often introduces heterogeneous catalysis. Various authors have developed this experiment for about 30 years. However, regardless to its toxic effects the use of methanol in this experiment poses some hazards, e.g. the formation of formic aldehyde during the reaction. Due to the hazard classification of methanol and formic aldehyde, the realization of this experiment in chemistry classes should be considered as critical. This post now presents a new school experiment on the oscillatory reaction of alkanes with atmospheric oxygen by resorting to historical context‐knowledge on the heterogeneous catalytic effects of platinum. The use of household petroleum ether also allows students to do the experiment from the 4th grade onwards and simplifies the handling. [ABSTRACT FROM AUTHOR]

Keywords: heterogeneous catalysis; oscillatory reaction; historical context-knowledge; substitution; Heterogene Katalyse; Oszillierende Reaktion; Historischer Erkenntnisstand; Substitution EN heterogeneous catalysis oscillatory reaction historical context-knowledge substitution DE Heterogene Katalyse Oszillierende Reaktion Historischer Erkenntnisstand Substitution 659 659 1 10/19/22 20221001 NES 221001 B Das Titelbild b zeigt den Moment der Verpuffung während der Verbrennung von n-Pentan am Platindraht als Katalysator. Dieser und weitere Versuche werden in der Rubrik "Das Experiment" vorgestellt. Heterogeneous catalysis, oscillatory reaction, historical context-knowledge, substitution. [Extracted from the article]