A few weeks ago, I passed by a stall that sold homemade skin care products – lotions, bath salts, etc – at the weekend farmer’s market.
Struck by the high prices of the bath bombs, under to $5 for the bigger sizes, I decided to research how to make them myself. Putting in keywords ‘bath bomb diy’ into Google immediately yielded pages upon pages of results ranging from recipes, discussions, reviews, videos and gorgeous step-by-step photos.
I had baking soda, rose essential oil, rose petals and, of course, water at home. Buying the remaining ingredients – epsom salt and citric acid – on Amazon was also easy enough.
All ingredients collected, I followed the instructions online to mix everything together. I took the liberty to add a bit more water than called for, thinking there’s no way one teaspoon of water is enough to emulsify all the dry ingredients.
For expert bath bomb makers, you probably know what happened next. For first time novices, keep reading to avoid the same mistake I made.
Everyone who’s been to or participated in a middle school science fair all know, or should be able to imagine, what happens when vinegar is mixed with baking soda.
Combine a base with a acid and a chemical reaction results creating heat. When the heat is not able to escape quickly enough, the reactants forms a gas before the reaction is over. Gases are more voluminous than solids, creating bubbles as they expand which, depending on the speed this occurs,can lead to an instant explosion.
In my excitement to get down to making mu very first bath bomb, I overlooked the two single most important ingredients combination on the diy list – baking soda and citric acid – a base and an acid.
After combining all ingredients, I jammed the mixture to the brim of mini mason jars, which I was using as molds, and twisted on the lids.
Setting this project aside, I went to do other stuff. Suddenly a loud POP sounded from the kitchen. Heading over, I was shocked to discover one jar had exploded and the others were fizzing over…
In my infinite wisdom, I decided, instead of twisting open the lids, to move the jars outside to my patio so when the next explosion occurred it wouldn’t cause major damage. In my mind as the time, the lids still needed to be capped so the mixture wouldn’t lose its shape as it dried. I just needed for the chemcial reaction to subside.
Needless to say, more lids were blown off in due time.
It was also near impossible to break the now hardened mixture away from the jar as extra water mixed into the citric acid had resulted in creating in too much gluing action. Not to mention that the core was still a bit soggy.
Salvaging the best I could of what remained, I combined more epsom salt and citric acid into a bowl, mixed in what I managed to scrape from the jars, and making sure my hands were extra dry (so as to not add a single droplet of water more to the mix) handpacked the resulting concoction into balls.
The bath bombs did expand a little after I set them down on the plate. But overall, the shape held and I had no exploding glass jars.
In summary, note to future self and others:
1. Do not mix in more water than called for, you can even try not using any water at all;
2. If using glass mason jars as molds, do not pack the mix in and then tighten the lids, leave the lids off;
3. (Digressing slightly here) 2 teaspoons of essential oil mixed against 1 cup baking soda and 1/2 cups each of epsom salt and citric acid is way too much perfume power. Cut down by at least 1 tsp. My kitchen still smells of rose a week.
Last but not least, good luck and have fun on your bath bomb adventure!