Russian YouTuber kreosan has a dangerous (read: badass) upgrade for the Mentos trick: regular Coke and propane. Yes, propane, the volatile petroleum fuel used in your gas grill. (At least, that’s what kerosan says it is in the video description. To us, it looks like butane—the similar fuel used in lighters—but we’ll defer to him on this detail.)
If you carefully add some liquid propane to the top of a Coke bottle, you can create a powerful jet of foam by turning the bottle upside-down. The propane then quickly converts to its gaseous state, exploding out of the bottle-neck and propelling the rocket into the air.
Needless to say, this doesn’t look particularly safe. Since this video already includes one broken window, this is a trick to experiment with at your own peril.
Screengrab via kreosan/YouTube