This fun activity is great for the whole family!  It’s very easy to set up and allows for a lot of independent experimentation.  Even the youngest child can have fun squirting the colored vinegar into the baking soda and watching it fizz.  Parents and older kids can use the baking soda as a canvas for creating bubbly and colorful designs.  But be aware, this one rates high on the messiness scale, especially if you are dealing with younger children who might ‘accidentally’ squirt their colors outside the pan.  I recommend using eye droppers for the littlest scientists in this case.

For St. Patrick’s Day you can stick with green food coloring, or use all the colors to make a Leprechaun rainbow!

 

LEARN SCIENCE VOCABULARY:

Carbon Dioxide (CO2) gas – The bubbles that form when the colored vinegar reacts with the baking soda are carbon dioxide gas. These are the same gas bubbles that make soda pop fizzy, and the same gas that we humans (and all other animals) breathe out!

Chemical Reaction – When two things come together and change into something else, this is a chemical reaction.  In this case, it is vinegar (acetic acid if you want to sound smarty-pants) and baking soda (sodium bicarbonate, for you smarties) meeting up to produce carbon dioxide gas to make bubbles!  (This reaction also produces salt and water, which will be left behind in your pan.). Things that have gone through a chemical reaction are permanently changed!

Effervescence – This is a fancy word for bubbles and fizzes. (And a great word to hear your 3-yr-old try to say!)

MATERIALS NEEDED:

• White vinegar
• Baking soda
• Food Coloring
• Any sort of pan or dish with sides (you may want more than one if you have several small children who don’t like to share… paper bowls would work great)
• Plastic cups
• Pipettes or eye droppers (Assuming you don’t have pipettes laying around, you could also use those plastic syringes that come with infant Tylenol… if you are like me, you have several of them hoarded away for just this kind of thing!)

HOW TO MAKE IT:

1. Pour a hefty amount of baking soda into the pans or bowls to cover the whole bottom.
2. Fill the plastic cups with about 1/4-1/2 C of vinegar and add color to each one.
3. Pipette out the colored vinegar and squeeze into the baking soda to make your designs!

                    

THE SCIENCE BEHIND IT:

Mixing vinegar and baking soda is one of the most common household science experiments…it is the backbone to the classic paper maché volcano.  It is actually a rather complex chemical reaction, where each substance (the vinegar and baking soda) is trading molecules and becoming completely different substances, in this case carbon dioxide gas, salt and water.  Preschoolers may not care much about the molecular science behind the reaction, but this is a great opportunity to teach about identifying gasses as something separate from liquids and solids. Once the design has stopped reacting (bubbling), they will notice holes or craters.  These holes are formed by the escaping carbon dioxide gas, proving gas does have volume and take up space. The effervescence they can observe in this activity is similar to what they would find in a fizzy drink or even by blowing bubbles into their milk or water (as I’m sure all my readers encourage their children to do in the name of science!).

NOTE: This activity is also a great one for experimenting with color mixing.  Kids will naturally want to mix colors together, either in the pan or by pouring the vinegars together.  I say, let them do it!  (I will post more activities on color mixing soon.)