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๐Ÿฅค
๐Ÿงช ChemistryMedium

Awesome Fizzy Bath Bombs Challenge

25 minutes 8 materials Ages 8-12

โš ๏ธ Safety Warning

Test on a small skin area first for allergies. Use skin-safe essential oils and food coloring only.

All experiments require adult supervision.

Materials You'll Need

Gather these 8 items before starting

๐Ÿ’ก Also called sodium bicarbonate - found in baking aisle.
๐Ÿ’ก Make sure this item is clean and ready before starting.
๐Ÿ’ก Found in the baking aisle - also called corn flour.
๐Ÿ’ก Vegetable or cooking oil is perfect for this.
๐Ÿ’ก Vegetable or cooking oil is perfect for this.
๐Ÿ’ก Liquid food coloring gives the best results.
๐Ÿ’ก Make sure this item is clean and ready before starting.
๐Ÿ’ก Use room temperature water unless specified otherwise.

๐Ÿ’ก Tip: Check off items as you gather them to stay organized!

Step-by-Step Instructions

Follow these 8 steps carefully

1

For this awesome version, in a large bowl, mix 1 cup baking soda, 1/2 cup citric acid, and 1/2 cup cornstarch.

๐Ÿฅ„Tip: Stir gently but thoroughly until well combined.
2

In a small bowl, mix 2 tablespoons melted coconut oil with a few drops of essential oil.

๐Ÿฅ„Tip: Stir gently but thoroughly until well combined.
3

Add food coloring to the wet mixture and stir well.

๐Ÿฅ„Tip: Stir gently but thoroughly until well combined.
4

Very slowly drizzle the wet mixture into the dry ingredients, stirring constantly.

๐Ÿฅ„Tip: Stir gently but thoroughly until well combined.
5

If the mixture fizzes, you are adding the liquid too fast โ€” slow down!

๐Ÿฅ„Tip: Stir gently but thoroughly until well combined.
6

The mixture should feel like damp sand and hold together when squeezed.

๐Ÿฅ„Tip: Stir gently but thoroughly until well combined.
7

Press firmly into molds or muffin tin cups.

๐Ÿ‘‡Tip: Apply steady, even pressure. Don't press too hard!
8

Let dry for 24 hours, then pop out and drop in a bath to watch them fizz!

๐Ÿ‘€Tip: Take your time to observe carefully. What do you notice?

โœ… Remember: Take your time with each step and ask an adult for help if needed!

The Science Behind It ๐Ÿ”ฌ

Bath bombs work through the same acid-base reaction as the baking soda volcano! Citric acid (the acid) and baking soda (the base) are kept separate in dry form โ€” they cannot react without water. When you drop the bath bomb in water, the water dissolves both ingredients, allowing them to react and produce carbon dioxide gas bubbles. The cornstarch slows down the reaction so it fizzes longer instead of all at once. The oils and colors disperse in the warm bath water, making it feel luxurious. This is applied chemistry you can enjoy every day! This variation explores the concept further by introducing new variables and measurements.