Teach:
Tell students that there is a way to turn dirty water in to clean water naturally. It is called condensation. Define condensation and spend a few minutes discussing the concept with your students before you begin. Tell the students that they are going to witness condensation in action. This is a supplemental experiment to use when teaching about water, condensation and evaporation.
Materials:
- Dirt
- Water
- Large pan
- Small cup
- Two rocks
- Plastic wrap
- Metric Ruler
- Notebooks
- Pencils
Procedure:
- Find a large pan. The pan must be bigger than the small cup that will be placed inside of the pan.
- Collect dirt and water and mix them together in a bowl. Make the water dirty and begin to pour the dirty water inside the pan.
- Have a student hold a metric ruler in the pan and have another student continue pouring the muddy water into the pan until the dirty water line reaches four centimeters.
- Have a student volunteer place a small cup in the center of the pan. If it does not stay in place, then place a rock in the center of the cup; this should hold the cup in place.
- Securely cover the top of the pan with plastic wrap.
- Add one more rock on the top of the plastic wrap where the cup is below it. This will make the plastic wrap come down over the cup, so that when the condensation occurs, the water droplets will fall into the cup and not back into the dirty water.
- Set the pan in an area that receives a lot of sunlight.
- Check the pan before you leave school for the day and again the next morning. Do you see any clean water inside of the cup?
Review:
Review condensation and how the water evaporates, but the dirt does not.
