Who knew that a geyser would result from dropping Mentos into a bottle of pop? It turns out that dropping a roll of Mentos into a bottle of pop releases the carbonation, causing the pop to gush into the air. Interestingly enough, diet pop works much better than regular pop. Mythbusters theorizes that cause behind this phenomenon is that the sugar in regular pop prevents fast bubble formation and the stickiness of the sugar contains the carbon dioxide bubbles better compared to the artificial sweetener of diet pop. The Mentos and Diet Coke (or Pepsi) experiment has gained popularity with the website Eepybird.com, where scientists turn the experiment into an art with its fountains and geysers. Scientists have tried it, and you can try it at home too! But first, check out this neat video for inspiration:



You will need:

  • One roll of Mentos mints
  • 2L bottle of diet Coke or Pepsi
  • A piece of paper


  1. Go outdoors onto a grassy area to avoid mess.
  2. Open the bottle of pop and place on the ground.
  3. Open the roll of Mentos.
  4. Roll the piece of paper into a tube to hold all of the Mentos. You want to make it loose enough so that you can drop all the Mentos into the bottle at the same time.
  5. Before you drop the Mentos into the bottle, tell everyone to stand back. Place the tube of Mentos over the open bottle of pop, but don’t drop the Mentos in yet (you can place your finger over the bottom of the tube to keep them from falling into the bottle). On the count of three, drop all of the Mentos into the bottle at the same time and move back.
  6. Watch and enjoy! The experiment is successful if the pop fizz shoots out of the bottle like a geyser. If it doesn't work the first time around, don't worry! It can be tricky placing all of the Mentos into the bottle at the same time. Try, try again (like in the video above).
  7. Remember to clean up the mess afterward (and if you like, you can still consume the bottle of pop).

How It Works

There has been great debate how exactly this works. The most common explanation of this 

Mentos and pop(89472)Credit: sciencekids.co.nz

experiment is that the gum arabic in the Mentos candy makes the carbon dioxide bubbles in the bottle of pop form faster because it breaks the surface tension. Also, the rough surface of Mentos candy contains tiny cracks that allow carbon dioxide bubbles to form. When the Mentos interacts with the pop, bubbles form on the candy. More and more bubbles form as Mentos interacts with the pop. When the Mentos are dropped at the same time, the carbon dioxide bubbles and Mentos interact at a very sudden rate, causing the fizz to shoot into the air, which is why the experiment works when you drop the Mentos into the bottle at the same time rather than one at a time.

So have fun with this science experiment, and do try this at home (home refers to the outdoor part of a home, rather than indoors).