Today, you are going to . . . MAKE A VOLCANO!  All you need is a mountain, a drill the size of a house, clothes that will not melt in lava, and . . . What was that?  You do not have any of those things?  I guess you will just have to make a model volcano instead.  These things are still pretty cool, and they will not melt your shoes.

Let's get all of our stuff together.  First you will need some baking soda, which is a solid white powder that we use to put out fires and to make some baked goods rise.  You may also find it in refrigerators, soaking up bad smells.  All by itself, it does not do much.  You know, besides puff up your cookies  .

Make sure you use baking soda, not baking powder!

Sodium bicarbonate is the chemical name for baking soda.  It is a base.  It's low on the pH scale, which is a way to measure how many hydrogen ions are in something.  If there are not many, then it is a base like a soap.  If there are a lot, then it will be an acid, like the stuff that eats through metal.  Like I said, baking soda is low on this scale.  Not so low that your soda bread will taste like soap, but not so high that it will eat through the table.

You only need one more thing.  Vinegar is a liquid that's an acid.  It is used in salad dressing and for cleaning things.  It can also take out spots in the carpet, clean windows, kill weeds, scare away ants, and many other things.  Take that, baking soda!  If your volcano blows up all over the place, you can tell your teacher or parent that it's really cleaning everything!  Then they might not be so mad.

I don't think the volcanos in Hawaii use vinegar.

Acetic acid is the scientific name that we use for vinegar, which is a weak acid.  It has some hydrogen ions in it, but not too many.  That way you can clean with it, but it will not eat through your skin.  Still, do not try to use it to make bread rise.  Maybe just dip the bread in after.  So now we have something with a lot of hydrogen ions and something with not a lot at all.  What do you say we put these two together . . .

Now, before you do that, let me tell you what's going to happen.  When these two come together, they will make a salt and something else totally different.  Carbonic acid is one product that comes from mixing baking soda and vinegar.  It is what makes soda pop bubbly.  The stuff that made the baking soda and the vinegar are still there, but now they are all scrambled up.  When you mixed together these two things that are both on different sides of the pH scale, the product jumps to the middle of the pH scale.  Something that changes that fast, well . . .

It turns out this new stuff cannot hold together.  After the first step, the product changes again.  Unstable means something that will soon change or fall.  This could be a shelf on a wall that is about to fall, or a kid on a bike for the first time or how your parent or teacher feels if you do not warn them that you are going to make a volcano.  The carbonic acid cannot stay the way it is when it touches air.  Right away, it starts to break down into water and a gas.  These turn into bubbles that fizz up and . . .

Well, I do not want to give away all the surprises.  Just be warned that you will make something that's a lot like a volcano! . . . with less burning and (a little) less mess.  Find a large bowl and place it outside away from everything or a on floor that can be easily mopped.  When you mix baking soda  with vinegar you come out with gas and water!  Oh, have an grown-up around and a towel.  This volcano may not melt through your shoes, but it will still blow up all over the place.


Dale-Chall Readability Index: 5.15 Raw Score; 5-6th Grade Level

Science Kids.  "Baking Soda and Vinegar Volcano"  Science Kids, 2011.  <>'

Ducksters.  "Acids and Bases"  Ducksters, 2012.  <>