“Then he got an idea! An awful idea! The Grinch got a wonderful, awful idea!” He decided to take a bath to warm his heart :) Not really, but if he saw these gorgeously green, marshmallowy scented bath bombs. I don’t think he would hate Christmas so much! Enjoy the Christmas holidays with these Grinch Bath Bombs. They’re a wonderful way to explore sensory science with a festive spin.
The Science Behind the Fizz of Bath Bombs
Ever wondered what makes bath bombs fizz? It’s science! The bubbles come from a chemical reaction between the citric acid (C6H8O7)and the baking soda (NaHCO3, a base called sodium bicarbonate). The reaction starts when the bath bomb gets wet and the reactants are allowed to come in contact. When they react, they combine to create sodium citrate (Na3C6H5O7) + water (H2O) + carbon dioxide (CO2). It’s the carbon dioxide that offgasses as bubbles, giving you that fizz. Adjusting the amount of cornstarch in a bath bomb controls how fast the reaction takes place because it interferes with the contact between the citric acid and baking soda.
Grinch Bath Bombs Supplies Needed
- 12 ct mini muffin silicone mold
- 1 cup baking soda
- 1/2 cup epson salts
- 1/2 cup cornstarch
- 1/2 cup citric acid
- 1/4 cup fractionated coconut oil (You need this kind of coconut oil because it’s a liquid at room temperature.)
- 1 teaspoon water
- 1 teaspoon marshmallow flavor oil (or you can use your favorite essential oil)
- Green soap colorant
- Wilton jumbo hearts sprinkles (I bought mine in store at Michaels, but you could use these instead.)
Yields: 1 dozen
How to Make Grinch Bath Bombs
1.  Add the baking soda, epson salts, cornstarch and citric acid to a medium mixing bowl. Whisk to combine.
2.  In a small bowl, add the coconut oil, water, marshmallow oil and green soap colorant. Stir to combine.
3.  Add the oil mixture to the dry ingredients, one tablespoon at a time. You want to add the oils slowly so you do not activate the bath bombs. Whisk the entire bath bomb mixture for about 3 minutes or until you have achieved your desired shade of green. The mixture is ready to mold if it clumps like dry sand when you squeeze it in your hand. If it doesn’t clump, add an additional 1 teaspoon of water and whisk again to distribute.
4.  Before transferring the mixture to the silicone molds, add a jumbo heart sprinkle to each mini muffin cup. Cover each heart with the bath bomb mix and press the mixture down firmly with your fingers. Allow to air dry overnight.
5. Â Carefully pop out each Grinch Bath bomb from their molds and store in an airtight glass jar.
How to Use Grinch Bath Bombs
First up, read The Grinch!! Then grab some cozy jammies and run the bath. Then place a Grinch bath bomb into your warm bath water. Enjoy the sweet aroma of marshmallow! The baking soda and epson salts will relax and soothe your tired muscles. The coconut oil will moisturize your skin. ENJOY!!
More Ways to Celebrate Grinch Day
We love the Grinch around here… It’s a must read in December and usually on Christmas eve, too because it helps us remember that being together as a family is what is important, not all the presents and such, that seem to take over. Here are 15 Ways to Celebrate Grinch Day to make reading The Grinch even more fun.
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