Baking soda volcano

How to make it

1. 

   1

   Build the mountain

   Stand the bottle in a pan. Mold dough or clay around it into a volcano shape. Keep the top open.

2. 

   2

   Load it

   Use a funnel to pour baking soda into the bottle. Add the dish soap and a few drops of red coloring.

3. 

   3

   Make a guess

   Ask: how high will it go? Write the guess down.

4. 

   4

   Erupt it

   Pour the vinegar in quickly and step back. Foam bubbles up and spills down the sides.

5. 

   5

   Try it again

   Rinse and try with more baking soda or warm vinegar. Compare which one foams more.

6. 

   6

   Talk about why

   Vinegar is an acid and baking soda is a base. When they meet, they make carbon dioxide gas. The soap traps the gas in bubbles, so you get foam.