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Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A significant challenge for the global community is the increasing demand for clean and renewable energy technologies. However, a lack of knowledge of these technologies threatens to impede their adoption. The development of cheap, effective, and easy-to-use chemical and electrochemical storage technologies is crucial if countries are to move away from fossil fuel electricity production. In this paper, we describe simple classroom-based learning systems that can be used to demonstrate the power-to-gas concept and its ability to greatly enhance the practicability and sustainability of other renewable energy systems. Most renewable energy systems can only produce energy sporadically and at specific locations; however, the power-togas concept uses hydrogen, obtained by electrolysis, to produce methane via the Sabatier reaction. We also demonstrate how this "dream reaction"--through the use of renewable energies such as solar and wind--can produce industrially and energetically desirable methane from hydrogen and carbon dioxide. The power-to-gas concept can be easily replicated in both educational and informal settings to encourage more grassroots and scholastic interest in the development of these vital technologies.

This article discusses a school experiment on carbon dioxide (CO2) absorption as an example of gas absorption experiments in the classroom. The experiment aims to illustrate the process of CO2 absorption and consider relevant factors such as temperature and concentration. Students can use a newly developed measuring system to independently carry out and quantify the absorption process. The experiment highlights the interdisciplinary work between the subjects of Science and Technology and Chemistry. The text describes an experiment on CO2 absorption using a sensor box and Arduino measurement device. The experiment involves connecting the components, setting the parameters, and measuring the CO2 concentration. The results can be displayed on an OLED display and recorded on an SD card. The experiment explores the absorption process using different parameters such as absorption medium, concentration, temperature, and amount of absorbent. The experiment is flexible and can be used for industrial CO2 purification or atmospheric CO2 reduction. The text also highlights the importance of sensor technology in visualizing invisible natural processes. The experiment is designed to be user-friendly and suitable for educational settings. [Extracted from the article]

Energy supply is one of the central challenges of current and future generations. It is formulated as one of the goals of the 2030 agenda in the sustainable development goals. If renewable energies are used for the electrolysis of water, the (green) hydrogen produced in the process can make an enormous and clean contribution to the energy supply. The storage of hydrogen is problematic and storage in the form of metal hydrides represents a promising perspective. This storage technology already exists for the didactic field and is used in the so‐called Hydrostik. The Hydrostik is suited very well for practical school use, as it has the format of a classic battery, can be flexibly transported and stored. When changing rooms at school or university, or even on lecture tours, the hydrogen source can thus be carried along without any problems. This represents a bridge between an innovative technology and fields of application in schools. This article explains how hydrogen storage works in the Hydrostik and presents some classic school experiments using the Hydrostik. Furthermore, thermodynamic aspects are highlighted. The visualization of the processes is supported by various digital components (animations, AR etc.). [ABSTRACT FROM AUTHOR]

Thermochromic mixtures are designed in a way that a color former is reversibly or irreversibly converted from a colorless to a colored state when combined with a developer under the influence of heat. In a simple experiment, the influence of solvent polarity on the color behavior of thermochromic mixtures is shown. In a non‐polar solvent, the color former is separated from a solid phase of the developer. When a polar solvent is added, the developer dissolves and is transferred to the liquid phase of the color former, creating the colored compound that is stabilized in the polar phase. Further addition of polar solvent leads to discoloration since the developer is more soluble in the solvent mixture. Therefore, the metastable dye‐developer complex dissociates, and the mixture gets colorless again. This aesthetic experiment provides a motivating introduction to the subject of thermochromic mixtures. [ABSTRACT FROM AUTHOR]

This article discusses the examination of energy carriers like hydrogen, natural gas and LPG in regards to their combustion enthalpy with simple school experiments. As a continuation of Part I of the comparative analysis of the energy carriers hydrogen, natural gas and LPG, the measurements and results will be optimized in this publication. The optimization of the measurement results succeeds with more elaborate experimentation material. Therefore, the experiments will be more demonstration experiments rather than student experiments. Due to the use of the combustion calorimeter the results are close to literature values for calorific values. [ABSTRACT FROM AUTHOR]

Copyright of Chemkon - Chemie Konkret is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Managing the energy supply is one of the most significant issues and a global challenge for humanity in the 21st century. With the "Energiewende" (best translated as 'energy transition'), Germany pursues the goal of replacing fossil and nuclear energy with renewables. Thus it is very important to integrate the topic into the syllabus of schools and universities. Since renewable energies are not available at any time, it is necessary to search for energy storage systems. In this respect, the "Power to Gas"‐concept seems to be one of the most promising solutions. We provide two approaches to realise these highly relevant reactions as a school experiment. Eine zentrale Aufgabe für uns Menschen des 21. Jahrhunderts ist es, die Energieversorgung in den Griff zu bekommen. Besonders die nächsten Generationen müssen innovative und intelligente Lösungen für eine nachhaltige und auch langfristig vertretbare Energieversorgung entwickeln. Demzufolge ist es unerlässlich, dass diese Themen in die Schul‐ und Hochschulcurricula implementiert werden, sodass fachliche Grundlagen vermittelt werden sowie eine frühzeitige Auseinandersetzung mit dieser Thematik erfolgt. „Power‐to‐Gas" gilt als eine Schlüsseltechnologie für das Gelingen der Energiewende. Erste Experimente, das „Power‐to‐Gas"‐Konzept mit schulischen Mitteln zu veranschaulichen, werden in diesem Artikel präsentiert. [ABSTRACT FROM AUTHOR]

This proof-of-concept study presents a new method of making latent fingerprints visible on thermal paper by brief ly immersing them in hot tap water. When this technique is used, a dark positive impression appears while the paper remains white and the imprint is preserved. Various factors, such as the inf luence of time since deposition and the persistence of the developed impression, were investigated. Optimal results were achieved with fresh to several hours old fingerprints. For impressions that were several weeks old, this method was not sufficiently reliable. The brightness and contrast of the developed fingerprints changed within the first week after development. The contrast of faded impressions could be increased in 75% of the samples by re-immersion in hot water. On low-sensitivity thermal papers, such as parking tickets, no fingerprints could be developed that would be sufficient for identification. Additionally, because of the need to pretest a portion of the specimen to determine the adequate developmental temperature by cutting off small paper samples, further research is needed to avoid this damaging of the evidence. [ABSTRACT FROM AUTHOR]

Energy provision and supply is an important topic both for society and education. This article presents school experiments for comparative research of hydrogen, methane and liquefied gas in regards to their combustion enthalpy. We focus on the mass‐ and volume‐related (respectively molar related) energy density, which can diverge. The experiments can be performed with simple materials and are suitable for class room tutorials and demonstration experiments. [ABSTRACT FROM AUTHOR]

Thermal papers contain a three‐component thermochromic mixture of a pH‐sensitive color‐changing leuco dye and a weak acidic developer dissolved in an aliphatic solid solvent‐matrix. Acetone vapors are able to dissolve the solid phase of the solvent, thus allowing the color reaction by the interaction of leuco dye and developer and the formation of the metastable colored dye‐developer complex. At the same time the thermal paper turns black. Renewed evaporation of acetone on the already blackened thermal paper releases the developer from the dye and enables thus the formation of the colorless form of the dye, which results in local discoloration. Competition between the dye−developer and developer−solvent interactions is the basis of the coloring behavior of such thermochromic mixtures, where this experiment provides a suitable and fascinating introduction to the topic in chemistry classes. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Translation abstract The 'Energiewende' is an important subject in Germany and many other countries. The energy supply and the energy storage are one of the main challenges for future generations. For this reason, it is very important to include these topics in the curricula of schools and universities. The following article presents the 'Power to Gas' - concept as one option for energy storage of renewable energies. We introduce two ways to realize these high relevant reactions as a school experiment. Furthermore, we present several possibilities to identify and differentiate between the products. [ABSTRACT FROM AUTHOR]