Science of Coke and Mentos

As a child I was amazed when a classmate dropped Mentos in a bottle of Coke and he got this huge fountain spray with all the foam coming out.

Only when I got older did I discover that there is a science to all of this.

Experiments in Mythbusters suggested the chemicals responsible for the reaction are gum arabic and gelatine in the sweets, and caffeine, potassium benzoate and aspartame in the Coke. But there have been no rigorous scientific studies of the reaction until now.



In layman's term, the prime factors that drive the fizzy plumes from Coke bottles: the roughness of the sweet and how fast it plummets to the bottle's base.