During the event “II Virada Científica” promoted by University of São Paolo at October, 17th and 18th the CEPID-Redoxoma group was Involved in science diffusion activities. About 160 people visited our activities during the event. The contribution of Cepid Redoxoma occurred in promoting experiments in a dark room named “Free, radicals and light”, two lectures named The fat, the slim and healthy – a conversation about metabolism, Sex, Chemistry and Power and presenting two educational games – Electron Transport Chain and ChemCards.
Experimental activities were designed for an audience of children, youth and adults, many of them families. Four experiments were conducted: amoeba; Blue Bottle; luminol – a criminal investigation and electrolysis of water que relied on the help of undergraduate monitors in chemistry and graduate monitors in chemical education.
All these experiments except amoeba involved redox processes and were visually beautiful.
In the amoeba experiment occurs a polymerization and a gooey product is formed with solid and liquid characteristics that children and adults love to play (Figures 1 and 2).
In the Blue bottle experiment (Figures 3 and 4) a redox process occurs. In an alkaline medium, glucose is oxidized to glicolic acid and promotes the reduction of methylene blue (blue) a leuco-methylene (colorless). With the shaking of the bottle, however, there is greater dissolution of oxygen in the solution which oxidizes the leuco-methylene to methylene blue and so the colorless solution turn around to blue again.
The experiment involving luminol allowed to simulate the work of the scientific police in a criminal investigation. Luminol is a substance used for the purpose of identifying traces of blood at crime scenes, even if in trace amounts. This is due to the phenomenon of chemiluminescence which is the production of light during a chemical reaction. The luminol reacts with hydrogen peroxide and iron acts as a catalyst. In this way, when the luminol and hydrogen peroxide solution comes into contact with human blood, using the iron present in hemoglobin, there is a chemiluminescence reaction and as a result we see an intense light being produced (Figure 5).
In the experiment of water electrolysis, it was possible to show in a simple and illustrative manner, the electrolytic decomposition of water proven by the distinct colors of indicators resulting of pH changes. It was used potassium nitrate, an universal indicator and clips connected to a source of direct current. By using an electric current, water electrolysis occurs and it is observed the formation of hydrogen and oxygen gas. The experiment was conducted in a petri dish on an overhead projector, allowing viewing by a large number of people (Figures 6, 7, 8 and 9).
During the lecture “The fat, the slim and healthy – a conversation about metabolism” Prof. Alicia Kowaltowski, from the Chemistry Institute discussed how our bodies become what we eat to what we are through metabolism. There was a discussion why the human body is metabolically and genetically programmed to accumulate “fats”, making obesity a health problem growing. Also she talked about what happens to some people, with “fast metabolism” that do not get fat easily.
In the lecture “Chemistry, sex and power” Prof Guilherme Marson, from the Chemistry Institute sought answers to what we see, with what we do not see in language that everyone understands.
The educational game presented on Electron Transport Chain has four sets of cards: complexes of the electron transport chain, oxidizable substrates (NAD+ and succinate) and Oxygen; ATP, effectors (inhibitors and uncoupled). The goal is to make ATP (Figures 10 and 11).
Chemcards is a cards and board game of chemistry and biochemistry, to learn and have fun (Figure 12).
Carmen Fernandez, Ph.D
Education and Knowledge Diffusion Coordinator of CEPID-Redoxoma
Associate Professor at Department of Fundamental Chemistry,
Institute of Chemistry, University of São Paulo, Brazil