Exploding Chalk

Instructions

Prepare Bags:

  • Add 1 cup cornstarch, 1 cup vinegar, and a few drops of food coloring to a ziplock and seal

  • Mix until cornstarch dissolves

Prepare Baking Soda:

  • Securely fold 1 tbsp baking soda into a square of toilet paper

Assembly and Reaction:

  • Drop the baking soda filled toilet paper into bag, seal, shake to mix

  • Place on flat surface

Observation:

  • The bag fills with gas and explodes!

Materials

  • White Vinegar

  • Baking Soda

  • Cornstarch

  • Food Coloring

  • Tissue Paper

  • Ziplock Bags

Questions:

  • What would happen if you changed the amounts of baking soda or vinegar?

  • Think about bag shape and placement. Could you manipulate the bags to create different pattern types when it explodes?

  • What would happen if water was substituted for the cornstarch?

  • Could you use the chemical reaction between vinegar and baking Soda for other things?

What is happening?

When vinegar and baking soda mix, hydrogen ions react with sodium and bicarbonate ions, forming carbonic acid and sodium acetate. Carbonic acid decomposes into water and carbon dioxide gas, creating pressure on the bag as the gas is released, eventually causing the bag to explode.