Fizzy Chemistry


When Acids and Bases mix, a gas is released. This reaction is used in beauty products and baked goods.


Fizzy Kitchen | Part I

Fizzy Kitchen | Part II

Fizzy Kitchen | Part III

Fizzy Kitchen | Part IV

Activity: Bath Bomb

  • Drop Bath Bomb into a cup of warm water.  Observe
  • Follow Directions to make Bath Bombs

Activity: What will react?

  • Purpose:  how do you identify acids and bases
  • Procedure:  test common baking ingredients in your kitchen and observe how they react

Activity: Pop Tops

  • Purpose: Activate dry acids and bases
  • Procedure
    • Mix Acids and bases and observe the reactions

Activity: Elephant Toothpaste

  • Purpose: Yeast also produces a gas.  
  • Procedure: Observe a chemical reaction between yeast, Hydrogen peroxide and dish soap.

Activity: Acid/Base Indicator

  • Purpose:  Use red cabbage juice to identify acids and bases.
  • Procedure: Add and ½ fill test tubes with cabbage juice powder and shake.  Observe
    •  Add ¼ teaspoon of citric acid to one cup. Observe
    • Add  ¼ teaspoon of baking soda to 2ndcup.  Observe
    • Carefully pour both test tubes into the cup.  Observe

Bath Bombs Instructions (

Bath Bomb Recipe Ingredients and Materials

  • 1 cup baking soda 
  • 1/2 cup citric acid ( I substituted unsweetened lemonade mix)
  • 1/2 cup Epsom salt
  • 1/2 cup cornstarch
  • 3/4 tsp. water
  • 2 tsp essential oil (lavender, eucalyptus, rose are all popular for the bath)
  • 2 tsp oil (jojoba, sweet almond, coconut olive or even baby oil)( I used olive oil)
  • A few drops of food coloring.
  • A mold of your choice, such as regular or mini-muffin tins, candy pans, or round plastic molds specifically for bath bombs (Plastic Easter eggs work well)
  • Optional: Dried flowers or sugar cake decorations, like flowers or stars

Bath Bomb Instructions

Step 1: With the exception of the citric acid, mix the dry ingredients in a large mixing bowl. 

Step 2: Pour all liquid ingredients in a jar with a top. Close the jar and shake it vigorously.

Step 3: Pour the liquid mixture into the bowl of dry ingredients, and use your hands to combine it well. At this point, add the citric acid. You'll probably notice a slight fizzing reaction because of the citric acid. This is normal.

Step 4: Mash the mixture into your chosen molds very tightly. You may slightly overfill the molds and use a spoon or glass to press the mixture in as tightly as possible. Immediately loosen the bombs from their molds onto wax paper and let them dry overnight. Before use or wrapping, let the bath bombs dry for another day or two.

Step 4: Give them another day or 2 to completely dry before using them or wrapping them up as gifts.

No Citric acid recipe (sensitive skin and small children)

What will react?

Purpose: Test different “kitchen chemicals” to see what reacts with an acid (vinegar) and water.

Background:  Bath bombs fizz because of a chemical reaction when acids and bases mix.  This reaction produces carbon dioxide. Many recipes in baking rely on this type of reaction to make our baked goods rise.  


  • Use a variety of “white powders” in your kitchen (flour, *baking soda, *baking powder, powdered sugar,  citric acid (or lemonade mix), etc.
    • *best choices 
  • To test you can use:
    • Paint pallets with compartments
    • Ice cube trays
    • Mini muffin tins
    • Bathroom cups
  • Put each ingredient to be tested in two “cups” and label
  • In one “cup” add vinegar - record observation
  • In the second cup add water - record observation

What happened?

Most compounds will dissolve in water. Some will create an acid, others a base, others simply dissolve.   If your ingredient creates a base, it will react with the vinegar and “fizz”. If your ingredient fizzes with water, you have a mixture of acid and base.  

Try this:  

Successful baked goods require an acid and a base.  Mix your ingredients to see which ones react together. 

Pop Tops

Purpose:  Observe acid/base reaction 

Background: Acid and bases react together and create gas. Some dry ingredients when mixed with water will form either an acid or a base.  


You need:

  • Acid/base combination
      • Alka seltzer with water
      • Baking Powder with water
      • Baking Soda with vinegar
      • Baking Soda and citric acid with water
      • Spoon full of “Bath Bomb”

* Extra Fun:  add acid/base indicator or fizzing tablet

  • Something to “blow up”
    • Small zipper bag
    • “Film canister” (also sold as craft containers)
    • Plastic storage container
    • Plastic Easter egg
    • Anything with a top that can “pop” off!

Mix and observe.

Experiment with proportions to get the best reaction.

Elephant Toothpaste Science Experiment


  • 2 Tablespoons Warm Water
  • 1 Teaspoon Yeast
  • Food Coloring
  • Hydrogen Peroxide – Either 3% or 6%
  • Dish Soap
  • Empty Plastic Bottle
  • Funnel

Instructions (Do this experiment in the sink, a large dish pan or baking pan - quite messy!)

  1. Combine two tablespoons of warm water with one teaspoon of yeast and mix until the yeast is completely dissolved in the water.
  2. Pour 1/2 cup hydrogen peroxide into the empty bottle
  3. Add a few drops of food coloring into the bottle
  4. Add a squirt of dish soap into the bottle
  5. Pour the mixture of water & yeast into the bottle
  6. Sit back and watch what happens

Yeast is also used in cooking for high rising baked goods.  It is a micro-organism that produces gas (carbon dioxide) when mixed with warm (not hot) water. Hydrogen Peroxide is a compound that when exposed to light releases oxygen (also a gas).  When it is mixed with the yeast, it releases the oxygen MUCH faster. The soap captures the gasses and makes bubbles!

Activity: Acid/Base indicator

Acid/Base indicator

  • Purpose:  Use red cabbage juice to identify acids and bases.
  • Procedure: Add and ½ fill test tubes with cabbage juice powder and shake.  Observe
    •  Add ¼ teaspoon of citric acid to one test tube. Observe
    • Add  ¼ teaspoon of baking soda to 2nd test tube.  Observe
    • Carefully poor both test tubes into cup.  Observe

You can experiment with this using anything from the “What will react?” activity. More fun things to try are everyday food items like juice, candy, soda, antacid.  Kids are always surprised that their favorite sour candy is an acid!

Red Cabbage is a natural acid base indicator.  The powder is sold as a natural food dye and can be found online and from science supply stores (and in home chemistry kits).  I love it because I don’t need much and it lasts a long time. You can make your own using a head of red cabbage (it’s actually purple!). Coarsely  chop and steep in boiling water, then drain. I use bottled water because my home water is slightly basic and will change the color. It should look like purple Kool Aid.

Other natural acid/base indicators: 

Cranberry juice (use pure bottled, or make your own. Same directions as cabbage juice.

Hydrangea blossoms.  This flower changes color based on your soil pH.  Acid soil gives pink flowers, basic soil gives blue.  Neutral soil gives purple blossoms. I have done this experiment using the petals like litmus paper.