What Makes Pop Rocks Pop?

The crackling effect caused by eating an envelope of Pop Rocks is because of the carbonation that’s in the candy. There’s tons of little pressure bubbles inside of each Pop Rock and when you put it in your mouth, your saliva melts the candy, causing the bubbles to pop. And contrary to urban legend, eating a pack of Pop Rocks while drinking a soda didn’t kill Mikey; so, it’s safe to enjoy the candy, AND your soda.