i have an explanation for this one: softdrinks is an acid beverage / carbonated drink and a mentos is a base. try it and u will discover it. don't use diet coke or anything which is diet because its not anymore a carbonated drink. what else if you will be putting those stuff together to your stomach. chemically speaking acid + base = neutral right? but when added by heat or any compulsive reaction (stomach or high energy something) what shall happen? discover it by doing the expirement, hehe this info was released a year ago.