In the time of September 13-15 the 35th advanced training and lecture conference of the specialist group chemistry education of the GDCh took place in Karlsruhe. The working group was actively involved: Sebastian Böttger presented his poster "Again lemon battery - a clarification". By means of total reflection X-ray fluorescence analysis, it was possible to show which processes take place during the operation of the lemon battery. Contrary to many opinions, the lemon battery is not a zinc/hydrogen corrosion element. In the classical lemon battery (with a zinc sheet and a copper sheet), the diffusing atmospheric oxygen is reduced; hydrogen ions can only be reduced when the potential of the copper is low and oxygen is excluded. The lemon battery with an iron nail and a copper sheet is always an iron/oxygen element. The project was developed in cooperation with the Department of Chemistry and its Didactics at the European University of Flensburg.
The poster was awarded as one of 15 top posters (out of a total of 54 exhibited posters) and was presented in a 3-minute talk at the beginning of the conference.
