Color Changing Bath Bombs

To all of my fellow diy-bath bombers, I pass on my knowledge and wish you the best of luck!  I have been trying to make a decent bath bomb for several months now.  Always small batches... and only when someone wants to take a bath, lol.

While I seem to have a real knack for soapmaking, making bath bombs just isn't my forte. I found a great(?) recipe using baking soda, epsom salts, cornstarch, and citric acid. (I'll call it great because it is awesome in the bath).  And I must have tried a dozen or more ways to hold them together. Too much oil and they are super soft; too much water and they fizz out asap; not enough oil or water and they either fall apart or won't form at all!

I tried using coconut oil, olive oil, sweet almond oil, witch hazel - anything Google suggested might hold them together. Each time I ended up with another failed batch. Oh well, time to soak away another failure, lol.  At least they still work in the tub even if they are not so much to look at.

In a side experiment, I made some beautiful purple crystals (check that blog post out here) and thought, "these would look awesome in bath bombs!" (I also made some pink and blue and thought they would look great atop a bar of soap, but that is definitely a topic for another blog.)

So I made a new batch using my purple crystals.  They really did look great, too. Until my bath bomb fizzled up... without any bath water.  You can see the start of the end below :(

Finally, something clicked in my brain and I changed my search from "how to make bath bombs" to "how to make professional bath bombs." You would be surprised at the impact that one little word had. Right away, it became obvious that isopropyl alcohol was the solution to my problem! It was wet enough to hold everything together, but evaporated fast enough to prevent a reaction between the baking soda and citric acid.  Success!  Alright, time to put my successes together!  I whipped up a batch and it looked great! 

The next morning, it STILL looked great - and it was the same size - aka, not fizzing itself into an enormous glob - so I wrapped them up and set them aside for some longevity experimentation - would they still fizzle in a week? What about a month? These are things I had to know!

Yes, I can be really boring sometimes....

Don't worry. I won't bore you with the results. After a couple days I noticed my beautiful purple crystals were changing colors! Some had turned a brilliant pink while others had turned a gorgeous blue and still some had remained purple! Wow!

The baking soda (a base with a high pH) and the citric acid (an acid with a low pH) were slowly changing the color of my crystals! And when I threw one into the water, everything turned purple again (because the water is overwhelmingly neutral). Oh my gosh, I love chemistry!

Want to create your own?

You'll need:

2 Tbs baking soda

1 Tbs citric acid

1 Tbs cornstarch

1 Tbs epsom salts (or if you want to make your own color-changing salts, check here)

1/4 - 1/2 tsp. sweet almond oil

12 drops essential oils

1 tsp 91% isopropyl alcohol

Blend all the dry ingredients together with a whisk.  Add in the essential oils (I used 8 drops of lavender and 4 drops of eucalyptus) and the sweet almond oil.  I made some with 1/2 tsp, but thought it made my water a little too oily, so I toned it down a touch to a 1/4 tsp.

Continue to whisk until the oil is evenly distributed throughout the dry ingredients.  Slowly add in the isopropyl alcohol until the mixture packs together.  Mold it however you'd like.  Bath bomb molds will give you the look they have at the store, but muffin tins or even hand forming them work just as well.  Once out of the molds, I sprayed mine with a touch more alcohol to give the outside a bit of a crust so it would hold its shape, and I let them dry overnight.