Question #c4638
1 Answer
Coke does not actually have a chemical reaction with the mentos - it is a physical reaction called Nucleation caused by the rough surface of the mentos and the carbonation in the drink.
Explanation:
Coke is a carbonated drink, which means that it has CO2 (carbon dioxide) trapped inside it. The CO2 can escape if it encounters a Nucleation site (any spot with a high surface area in a small volume) by forming a bubble on it which eventually becomes large enough for the bubble to float up and escape.
Mentos are covered with such sites - the surface of the candy not completely smooth. Thus, the carbon dioxide in the soda quickly forms many bubbles as the mentos enter the liquid and sink through it. The bubbles quickly rush up out of the liquid, creating a fun and very messy geyser.
