Messy mixture: a dirty experiment.

1. Collect about 1/4 cup of dirt from outdoors

and put it in a clear jar with a lid.

2. Add about 1 cup of water. Put the lid

on the jar and shake it up.

3. Let the mixture settle for five to ten

minutes. Is there dirt in the water?

Where is most of the dirt?

4. Now add 1/2 cup of oil (vegetable oil will

work) to the jar. Put on the lid and shake

it up again.

5. After five to ten minutes, look at the

mixture. The oil layer will float on top of

the water. Where is the dirt now? Is there

more dirt in the oil or in the water?

6. Now add a big squirt of dishwashing

detergent. Shake again.

7. Let the Jar settle for five to ten minutes.

Where is the dirt now? Does the oil

layer look cleaner?

This experiment shows how dirt likes to stick to oil. Adding

detergent should have cleaned most of the dirt from the oil layer,

just like soap cleans the dirt from your oily hands.