# How does the Mentos-Coke explosion work?

We all might have seen this in some videos or in real life. But how exactly does this work? What is the chemical reaction involved?

And why is the reaction of Mentos with Diet Coke more vigorous?

From left to right: action of five Mentos candies (per bottle) with Perrier, classic Coke, Sprite and Diet Coke

Image source

• Complete speculation: perhaps one of the ingredients in Diet Coke acts as a catalyst for the conversion of $\ce{H2CO3 -> CO2 + H2O}$, and thus more of the carbonation is able to effervesce to form foam? – hBy2Py Sep 1 '16 at 15:04