Erupting Rainbows

Every March for the past few years we have created a Fizzing Rainbow. And let me tell you, the entire family loves this simple experiment! I know that I’ve said it before (and I’m sure I’ll say it again) but you can never go wrong with rainbows. And fizzing rainbows give me heart eyes for days! They are simply breathtaking and oh so fun to play with. 🙂 So basically what I’m saying is…if you combine baking soda, vinegar, and liquid watercolors – you create pure magic! And this year…we decided to up our rainbow magic game with these Erupting Rainbows!

How can you go from a simple fizzing rainbow to an erupting rainbow?!? With baking soda bombs! During the Easter holiday last year, Michelle @createlaughlearn shared these adorable bunny baking soda bombs that she made with her daughter. I knew right away that Michelle’s baking soda bombs would be a game-changer for our fizzing rainbow experiment…and I’ve been chomping at the bit for March to roll around again, so that we could give these bad boys a try.

These rainbows always put a big smile on our face! And according to our little nugget…they also make the leprechauns super happy. 🙂 I just can’t get over how beautiful the tray looks as each color flows out of its glass to join the others in one big pool of rainbow awesomeness! We could conduct this colorful experiment every day for the rest of my life and I don’t think I would ever get bored. Though that would require quite a lot of vinegar. So…I guess I’ll compromise and just watch this video on repeat.

FYI – the baking soda bombs take at least 24 hours to dry and harden. So make sure to get them ready one day prior to creating your erupting rainbows.

Supplies:

Baking Soda
Water
White Vinegar
Shamrock Silicone Mold (or any other type of silicone mold that you have on-hand)
Liquid Watercolors (food coloring also works)
Glasses/Cups
Tray (to catch the overflowing liquid)
Plastic Tablecloth (optional)

Instructions:

At least one day prior to creating an erupting rainbow, you will need to make your baking soda bombs. To do so, combine two cups of baking soda with 2 tablespoons of water, in a medium-sized bowl. Mix together until thoroughly combined. Place your silicone mold on a tray or cookie sheet. Using your tablespoon, scoop the mixture into the molds. Now this is the most important step…with your fingers, press the mixture firmly down into the molds. And I mean firmly. This one step will determine the fate of your baking soda bombs. 🙂 The mixture should be packed in as tightly as possible. Keep adding more of the mixture and packing it down into the molds until the molds are completely full. Set them aside to dry for at least 24 hours.
Once your baking soda bombs have dried for 24 hours (or more), carefully pop them out of the silicone molds. You may end up with a few broken shamrocks (and that’s ok – they are still perfectly usable). Of our eight shamrocks, two were broken. This could have been due to the fact that the shamrock molds themselves are a bit deeper than Michelle’s bunny molds, or maybe we just didn’t pack those two down as firmly as the others.
If you would like, lay a plastic tablecloth over your table to catch any spills that might escape from the tray. I highly recommend doing so…it makes clean-up a breeze.
Now it’s time to setup your rainbow. Grab six clear glasses or cups and place them on a tray (we like to place ours in an arch). Add a few squirts of liquid watercolor to the glasses in rainbow order (red, orange, yellow, green, blue, and purple), so that you end up with one glass of each color.
Fill the glasses approximately 3/4 full with white vinegar.
You’ve got your rainbow…now you just have to make it erupt! Place one shamrock baking soda bomb next to each glass. When you’re ready…quickly drop a shamrock into the red glass, then the orange, and so on down the line.
Sit back and marvel at your beautiful erupting rainbow!

The best part about this colorful rainbow experiment is that the fun doesn’t have to end after the first eruption!

The baking soda bombs take a long time to dissolve – you will be able to see them sitting at the bottom of each glass, once the initial bubbling and fizzing has dissipated. Thus, you can simply add more vinegar to each glass to create subsequent rainbow eruptions!