The Magic of Fizzy Bath Bombs Explained by Chemistry

Close your eyes. It’s 2017. “Sign of the Times” by Harry Styles is on the radio in the mall. It’s packed. You rush to the Lush store to grab their last sparkly bath bomb for your mom. Christmas is in two days. Give a listen to the “Bath Bombs” episode for a beginner-friendly explanation to find out how to make fizzy bath bombs.

Bath Bombs Podcast

Why do bath bombs fizz? What’s so special about Lush bath bombs anyway? Fun guy biologist Mr. Joe explains the chemical reaction that takes place during a bath bomb bubble bath. Basics, acids and neutralization. Plus, what is baking soda made of anyway? Try Amazon music —> — Send in a voice message: Support this podcast:

If you prefer to watch a visual version, fun facts about bath bombs can be found on our Youtube channel:

Creative Challenge

This week’s creative challenge is to write a creative story involving bath bombs.

Bath Bombs Creative Writing Challenge: write a creative story involving bath bombs.

When were bath bombs most popular?

Bath bombs spiked in popularity in 2017. Things have calmed down a bit, but every November, the bath bomb sales pick up again. 

Bath bombs are a “wellness” or beauty product to use while taking a bath. Not a shower, but a bath? 

Why are bath bombs fizzy?

When you drop a bath bomb in water, a chemical reaction happens. The chemical reaction is called neutralization. Neutralization describes when a basic substance is mixed with an acidic substance. 

Basic is essentially the opposite of acidic. There are many acidic foods you might know: lemons, oranges… and some acidic non-foods, like battery acid or stomach acid.

A basic item that we all know and love is Tums or alka-seltzer. These basic items will balance out an upset tummy.

baby inside white bathtub with water
How many adults take baths anyway?

Showers vs. Baths

In a study of 2,000 adults by Victorian Plumbing, only 32% of adults preferred taking baths over showers. 57% chose to shower. However, that only adds up to 89% so, I wonder if that survey had an option for “I never bathe.” Victorian Plumbing is based in the UK.

Showers are typically faster than baths, of course. And if you used a beautiful bath bomb, you’ll want to let it fizz out as long as possible.

How To Make A Homeade Bath Bomb Just Like Lush

Homemade bath bombs have a pretty standard recipe across-the-board. Cornstarch, essential oils, some type of neutral oil (coconut oil, almond oil, sunflower oil), bath salts, baking soda and a type of pigment (mica, food coloring). The most important ingredients are citric acid and baking soda: the basic and acidic ingredients. 

The only difference between homemade bath bombs and Lush’s “Intergalactic” bath bomb is the extra ingredients. Lush’s bath bomb has citric acid, corn starch, and various oils: peppermint, grapefruit, cedarwood… or others, depending on the “flavor” of the bath bomb.  

The acidic ingredient in Lush’s bath bombs, however, is Cream of Tartar.  

What is Cream of Tartar made of?

Cream of Tartar is NOT creamy, it’s a white powder. It’s a byproduct of wine-making and powder form of tartaric acid. Tartaric acid is found inside of grapes and most other fruits. After the winemaking happens, cream of tartar is left behind as a sediment (or “powder).

What is Baking Soda made of?

Baking Soda is just sodium bicarbonate. But that’s not a plant or anything, so where does it come from? Arm & Hammer, a big baking soda company, gets their baking soda from a mine in Wisconsin. Baking soda is found in the minerals nahcolite and trona.

Nahcolite and trona are refined into soda ash (sodium carbonate), then turned into baking soda (sodium bicarbonate).

One way to get baking soda is by flushing out a trona mine with hot water, then the substance crystallizes. The crystals will sink to the bottom. It’s basically a refining process over and over to remove the water until all that’s left is powder.

Trona is a CRYSTAL. It’s a yellow-whiteish looking rock. The same goes for Nahcolite. But nahcolite can come in a more pinky-purple hue. Kind of like pink himalayan salt, which is probably really similar. 

Sodium = salt. So technically baking soda is a salt. 

What is citric acid made from?

The last mysterious ingredient, citric acid is made from a fungus from fermented molasses. Although natural citric acid can be derived from regular citrus fruits like lemons or limes.