With this activity, students will use just a few ingredients to create an awesome chemical reaction explosion! This activity makes a mess so do it outside.

Materials Needed

Per Student:

1 sandwich sized zip-top bag (freezer bag works best)
¼ cup warm water
½ cup vinegar
3 Tbsp baking soda
1 tissue

A Few Per Group:

¼ cup measuring cup
½ cup measuring cup
1 Tbsp measuring spoon

Optional:

Extra bags of various sizes

Steps:

Go outside.
Put 1/4 cup of warm water into the bag.
Add 1/2 cup of vinegar to the water in the bag.
Seal bag and set aside.
Put 3 teaspoons of baking soda into the middle of the tissue.
Wrap the the baking soda up in the tissue by folding the tissue around it.
Open up the bag.
You will have to work fast now – partially zip the bag closed but leave enough space to add the baking soda packet.
Put the tissue with the baking soda into the bag and quickly zip the bag completely closed.
Put the bag in the sink or down on the ground (outside) and step back. The bag will start to expand, and expand, and if all goes well…POP!

Explanation:

Inside the bag, the baking soda and the vinegar eventually mix (the tissue buys you some time to zip the bag shut). When they do mix, you create what is called an ACID-BASE reaction and the two chemicals work together to create a gas (carbon dioxide – the stuff we breathe out). Well gasses take up a lot of space and the carbon dioxide starts to fill the bag. It keeps filling the bag until the bag can no longer hold it any more. POP!

Real World:

Acid-base reactions happen every day. Sometimes they make things explode, but sometimes they help to make something delicious! For example, when you make a cake or a quick bread, baking soda and an acidic ingredient (like buttermilk) create an acid-base reaction. When the gas is formed in the cake batter, it makes little bubbles that make the cake rise. It may not explode, but it’s still pretty great!

Optional:

Try it!

Redo the experiment with cold water. Does anything change?

What happens if you add less baking soda? More baking soda? How about vinegar?

Is anything different if you use different sized bags?

Adapted from CO2 Sandwich by Steve Spangler Science