Author: Carlos Cunha
Origin: PORTUGAL
Implemented in: Czech Republic, Finland and Poland
The aim is that students learn to draw graphs and to interpret a velocity graph. The lesson starts with a theme presentation in the form of a video and a discussion. After that the students have to carry out an experiment using different vinegar concentrations and the same mass of bicarbonate and record the mass evolution during reaction using their cell phone. The videos are used to up draw a table indicating concentration versus time. The same procedure can be repeated using another reagent concentration. During this GP students learn to be observant, to do hands-on work and solve problems, to interpret graphs and their results, and to use computers and mathematical concepts.
Success stories
The teachers who implemented this GP all applauded the idea of using mobile phones during the experiments, as they noticed that this was extremely effective and motivating for the students. According to a Polish teacher the students “were taught how to make graphs and avoid mistakes. The GP worked both with younger as well as older students because of the power of visible results, namely the carbon dioxide gas that we see bubbling and foaming as soon as we mix baking soda and vinegar together. Two common non-hazardous materials found in almost every kitchen help us understand the basic postulate of chemical kinetics that ‘The velocity of chemical reaction at a given moment of time is proportional to the concentrations of reagents raised to a certain power.’”
