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Ketchup and Baking Soda Volcano

Natural Orange-Red Nontoxic Lava

By Anne Marie Helmenstine, Ph.D., About.com

Ketchup contains vinegar, which reacts with baking soda to producelava for a chemical volcano.

Ketchup contains vinegar, which reacts with baking soda to produce an extra-special lava for a chemical volcano.

Anne Helmenstine
The acetic acid in ketchup reacts with baking soda to produce an extra-special type of lava for a chemical volcano. This non-toxic volcano recipe is sure to please!

Ketchup & Baking Soda Volcano Materials

  • small container (I used an empty travel-size bottle.)
  • volcano (You can mold it from clay or use a cardboard form.)
  • ketchup
  • baking soda
  • liquid dishwashing soap (optional)
  • water (optional)

Make the Volcano Erupt

This is really easy! Swirl together a squirt of dishwashing detergent (if you want foamy orange lava), ketchup, and enough water to achieve the desired thickness. When you are ready to start the eruption, add baking soda. Alternatively, you could mix together the baking soda, detergent, and water. Add the ketchup when you're ready for the eruption.

The 'lava' erupts slowly and steadily, rather than forcefully, so this is a nice volcano to make if you want a longer-lasting eruption.

How the Volcano Works

The ketchup contains vinegar, which is dilute acetic acid. The acetic acid reacts with the baking soda to produce carbon dioxide gas. The gas bubbles expand and rise through the liquid, bubbling out the ketchup.

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