We wrapped up our unit on rocks and minerals with a few quick hands-on activities today.
The first was our graham cracker earthquakes. The graham crackers represented the tectonic plates (part of the earth's crust) and we used blobs of white icing as the earth's mantle. The experiment demonstrates the forces that create earthquakes. It also shows the tension that can build up before a quake and the resultant debris created along a fault.
Our grand finale was the baking soda-vinegar volcano. Though it doesn't really demonstrate a true volcanic reaction, it was a fun way to wrap it all up.
I promised the students I would post the directions so they can, with permission, try a larger volcano at home (I kept them quite small and contained -- minimal cleanup!)
So, here they are:
1/4 cup vinegar (up to a cup if you have a large bottle)
2 tablespoons baking soda
jello granules (about a tsp or two; add more if you want more colour)
Mix the baking soda and jello crystals and use a funnel to get the mixture in the bottle. That's it. When you're ready for the erupting volcano, use a funnel to pour all the vinegar into the bottle at once, then take the funnel out quickly. The key is to get all the vinegar into to bottle as fast as possible and move out of the way. It won't explode, but lava bubbles do ooze out pretty fast once the reaction starts.