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How to Do the Classic Baking Soda Volcano Science Experiment

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For our creative STEM activities for kids series, I wanted to do science experiments for kids that were easy, but also impressive at the same time. This made a volcano science experiment a must.

We’ve made a volcano science experiment before, but this time, we decided to make it look a little more impressive by adding a play dough mountain around our bottle and making the inside of the volcano a deeper red.

How to Do the Classic Baking Soda Volcano Science Experiment. Every kid needs to try it! This version uses a Baking Soda and Ketchup Reaction.

How to Do the Volcano Science Experiment

Follow along with these instructions if you’re making a ketchup and baking soda volcano!

What Makes the Baking Soda and Ketchup Reaction?

What causes the volcano to explode in the volcano science experiment is the reaction between the baking soda and vinegar.

Baking soda is a base and vinegar is an acid. When a base and an acid are mixed, it creates a byproduct of carbon dioxide, which causes the mixture to overflow just like a shaken soda bottle.

When dish soap is added to the mix, it makes things even more foamy and bubbly.

Supplies for the Volcano Science Experiment

  • Ketchup or tomato paste
  • Vinegar
  • Dish soap
  • Baking Soda
  • Play dough
  • Small bottle
  • Funnel

How to Make a Baking Soda Volcano

Girl pouring vinegar into baking soda and vinegar volcano

Place about 2 tablespoons of baking soda into a bowl. Add about 10 drops of dish soap on top of the baking soda and about ¼ of a cup of ketchup or tomato paste.

Mix together gently with a spoon so you don’t make too many suds at once.

Cover the bottle with play dough and place it on a tray. We put ours in a garden box. Carefully pour the baking soda mixture into the bottle using a funnel.

Girl makes playdough volcano erupt

Add vinegar to the bottle slowly, a little at a time. We ended up adding too much vinegar to ours (as you can see in the video), which made our eruption a little less impressive.

Monkey loved seeing the science demonstration and had a lot of fun setting up the volcano and watching the reaction.

If you want to go further with this experiment, you can experiment with various additives to the vinegar and baking soda mixture to see if you can make the eruption more impressive or change the speed at which it leaves the bottle.

Watch our volcano erupt!

More Volcano Experiments for Kids

Colorful Snow Volcano Experiment Using Real Snow

Pumpkin Volcano Experiment for Kids

Easy DIY Volcano Slime Recipe that Really Erupts!

Apple Volcano Experiment

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