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Mt. Baker



Build a real working volcano

Now we're going to get a little messy. In this experiment we build a real working volcano. After mixing just the right amount of ingredients together, we'll add the final item to make our volcano 'blow its top' spewing red lava down the sides.
  1. First we need to create the 'salt dough'. Mix 6 cups flour, 2 cups salt, 4 tablespoons cooking oil, and 2 cups of water in a large bowl. Work the ingredients with your hands until smooth and firm. Add more water to the mixture if needed.
  2. Stand the soda bottle in the baking pan. Mold the salt dough around the bottle making sure you don't cover up the bottle mouth or drop any dough into the bottle. Take your time on this step and build your volcano with as much detail as you like.
  3. Fill the bottle most of the way with warm water mixed with a little of the red food coloring.
  4. Put 6 drops of the liquid detergent into the bottle.
  5. Add 2 tablespoons of baking soda.
  6. Slowly pour vinegar into the bottle and jump back quick!
Notice the red 'lava' that flows out of your volcano. This happens because of the baking soda and vinegar mixture. Mixing baking soda and vinegar produces a chemical reaction (a chemical reaction is a process in which one substance is chemically converted to another - all chemical reactions involve the formation or destruction of bonds between atoms) in which carbon dioxide gas is created - the same gas that bubbles in a real volcano. The gas bubbles build in the bottle, forcing the liquid 'lava' mixture of the bottle and down the sides of your volcano.