#188. Water Sandwich

Science, level: all
Posted by Krystal Wadsworth (kwdswrth@msuvx2.memphis.edu).
University of Memphis, Memphis, Tn. USA
Materials Required: 1/4 cup vegetable oil, 1/4 cup water, 1/4 cup honey, clear plastic cup, measuring cup
Activity Time: 15-20 minutes
Concepts Taught: Density

Directions: 1. Pour the oil, water, and honey into the cup.
2. Have the children watch the side of the cup.
What happened: The three different liquids have different densities, so they separated into layers. The oil is less dense than the water,so it floated to the top. The honey is more dense than the water, so it sank to the bottom. The water remained in the middle-a water sandwich!
Suggestions and variations: Try experimenting with different liquids to see which are more dense and which are less dense. When using liquids which are very similar in color (rubbing alcohol and salt water, for example), add a few drops of food coloring to one of the liquids so that it will be easier to see any layers which may form.
*This activity demonstrates that different liquids have different densities.