Add 2 teaspoons of baking soda and 2 teaspoons of citric acid to the foam cup. Add the half cup of water to the cup and stir. Is a chemical reaction taking place? How do you know?
In this cooking procedure, a chemical reaction is taking place because the citric acid and the baking soda are both chemical species combining together.
At the end a new produce is formed.
It is accompanied by a release of heat
The stirring helps to increase the rate of chemical reaction between the citric acid and baking soda