Objectives

To create a powerful reaction with the carbon dioxide in the soda

Materials

• Diet soda (2 liter bottles--three clear or two clear and one red)
• Mentos®-mint flavored-three packs 
• Food coloring-red and blue
• Tube for Mentos-need three (can be ordered online or you can create your own using tube and index card)

Procedure

Carefully open the bottles of soda and place red food coloring in one, blue food coloring in a second, and leave the third bottle clear (or white). Line them up on a table or on the ground, side by side. Place a package of Mentos® in each tube. Place an index card over the bottle mouths and carefully line up the tubes of Mentos® over the bottle openings. Pull the index card away and back away quickly! Watch the star spangled eruption. (This can be messy!)

Conclusion

You have created a reaction when the Mentos® come into contact with the soda.The structure of the candy is the most significant cause of the eruption due to the surface of the mints.They are covered with many small holes that increase the surface area available for reaction (nucleation sites) thereby allowing CO₂ bubbles to form with the rapidity and quantity necessary for a "jet" or "geyser" to spray out of the bottle.