Bubbling Density Concoction The bubbling concoction is a clever mixture of lessons. email to friend
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(Be sure to cover your work area before beginning this experiment!)

1. Pour corn syrup into the glass to a depth of about 1 inch (2.5 cm). Mix in several drops of red food coloring and mix well.
2. Sprinkle small measuring spoonfuls of baking soda on top of the corn syrup to a depth of about 1/4 inch (3/4 cm).
3. Gently pour water into the glass to a depth of about 1 inch (2.5 cm).
4. Add the vegetable oil next to a depth of about 1 inch (2.5 cm).
5. In a separate cup, use the blue food coloring to dye the vinegar.
6. Take the dropper and drip the vinegar into the glass. You will notice that blue blobs will slowly add up between the oil and water. Keep adding the vinegar and watch the results.
7. Next, take the dropper filled with vinegar and put it into the glass so that the tip is in the baking soda layer. Release the vinegar and see what happens.
8. Keep adding more vinegar and observe the foaming reaction.

How does it work?

This experiment shows density along with a chemical reaction. Notice that the lighter liquids float on top of the heavier ones which creates the separation in the glass. When you first add the vinegar, it drops through the oil but has trouble breaking through to the layer of water. Because of that, blobs of vinegar pile up at the bottom of the oil layer. When the vinegar is released in the layer of baking soda, a chemical reaction occurs that causes it to foam.