This classic science experiment is always a favorite activity for kids. And it’s easy to put together too! You only need baking soda, food coloring, water and vinegar. Kids will loving making this fizzy rainbow.

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Rainbow Baking Soda and Vinegar Experiment

Rainbow Baking Soda and Vinegar Experiment

Kids love doing this easy science experiment. Not only is it a fun activity but it’s a great learning exercise too. They also get to practice fine motor work by using a pipette or dropper.

To save steps, you can also do this experiment by using regular baking soda shaped into a rainbow. Then just add a few drops along the arches of the food coloring.

Baking Soda and Vinegar Experiment for Kids

The Science

What happens when you mix vinegar and baking soda?

You see the bubbling and foaming but what is causing this reaction? The baking soda (sodium bicarbonate) is a base while the vinegar (acetic acid) is an acid and what you are seeing is an acid/base reaction. Initially, the reaction makes carbonic acid which is unstable and breaks down into carbon dioxide (CO2) and water which is what creates all of the fizzing and bubbles as the gas leaves the water.

 

Add Vinegar with Dropper

Supplies Needed to do a Baking Soda and Vinegar Experiment

 

– Baking Soda – we like this large 5 lb bag for activities

– Food Coloring Gel (one in each color of the rainbow) – we like to use this liquid food coloring gel since it’s concentrated and makes the colors really vibrant

Dropper

– Water

– Vinegar

Baking Soda Experiment for Kids

Watch the Video Tutorial Here!

How to Do a Fizzy Baking Soda and Vinegar Experiment

1. Start by placing 1 cup of baking soda into a bowl.

Add Baking Soda to a Bowl

2. In a pouring cup, add 3 tablespoons of water. Mix in 1-2 drops of red food coloring into the water. If using regular food coloring, you may need to add more drops to make it more vibrant.

Mix Food Coloring and Water

3. Pour the food colored water into the bowl with baking soda and mix until the baking soda is dyed.

Add Food Coloring to Baking Soda

It should still be a powdery-like texture and look like the following:

Mix the Baking Soda Until Fully Mixed

Repeat the above steps for Yellow and Orange. 

For Green, Blue and Purple, mix only 1/2 cup of baking soda to 1.5 tablespoons of water (you don’t need as much of these colors to make the rainbow so you can halve the recipe above.

4.  Lay out the colors onto a white tray or baking sheet. Protect your table if needed so the food coloring does not go onto your table.

Add Baking Soda Mix in Rainbow Shape

 

5.  Put vinegar in a bowl and then let kids use a dropper to drop the vinegar onto the rainbow.

Add Vinegar to Baking Soda

Kids love seeing the reaction the baking soda and vinegar makes together!

Vinegar to Baking Soda

We love how easy this science experiment is to set up. And kids love to use the droppers to make the vinegar/baking soda reaction.

The rainbow version is a lot of fun to try! We hope you enjoy this easy science experiment!

 

More Science Experiments

Try this fun and easy Grow a Rainbow Experiment. You only need washable markers and paper towel!

Growing Rainbow Experiment

For another fun experiment, make some oobleck! 

How to Make Oobleck

Try a rainbow rain cloud in the jar experiment!

Rain Cloud in a Jar Rainbow