Blobs in a Bottle

 

(The world’s easiest lava lamp)

What you will need:
1 liter clear soda bottle
3/4 cup of water
Vegetable Oil
 Fizzing tablets (such as Alka Seltzer)
 Food coloring

Pour the water into the bottle.
Use a measuring cup or funnel to slowly pour the vegetable oil into the bottle until it's almost full. You may have to wait a few minutes for the oil and water separate.
Add 10 drops of food coloring to the bottle. The drops will pass through the oil and then mix with the water below.
Break a seltzer tablet in half and drop the half tablet into the bottle. Watch it sink to the bottom and let the blobby greatness begin! To keep the effect going, just add another tablet piece. For a true lava lamp effect, shine a flashlight through the bottom of the bottle.

From www.sciencebob.com