Clean the Water
In this experiment, you will be able to describe
the process that water treatment
facilities use to treat water for drinking and demonstrate the operation
of a water treatment facility.
- Paper (to record your findings)
- 2-gal. (8L) jug of water
- 2-liter plastic bottles
- Alum (a spice found in most supermarkets)
- 5 cups (600 mL) of soil
- Fine gravel
- Use the funnel to pour about 1.4 L of dirty water into the 2-Liter
plastic bottle with cap. The dirty water can be made by adding
five cups of soil to two gallons of water. Describe the appearance
of the water on paper.
- Put the cap on the bottle and shake for about 30 seconds. Continue
the process by pouring the water back and forth between two bottles
10 times. Record what part of the treatment
process this action represents.
- Pour the water from step two into a 2-liter bottle with the
top cut off. Add two tablespoons of alum to the water. Stir the
mixture slowly for about five minutes. What process
- Allow the water to stand undisturbed for 20 minutes. Observe
the water at five-minute intervals and record your observations.
What process is occurring
the bottom from another 2-liter or 3-liter bottle. Construct a
filter using cotton and the cheesecloth and plug the neck of the
bottle with the filters. Secure with a rubber band.
- Pour the fine sand over the cotton plug followed by activated
charcoal, coarse sand, fine gravel and coarse gravel. Clean the
filter by slowly pouring through 4-8 liters of clean tap water.
- Place the filter over the bottom part of another bottle. Without
disturbing the sediment in the container with the alum, pour the
top two-thirds of the water through the filter. What process
- After waiting until more than half of the water poured through
the filter has been collected, add two tablespoons of bleach to
the filtered water. What part of the treatment
process does the addition of bleach represent?
- Record the differences in appearance and odor. Examine both
treated and untreated water with a microscope and record your
- Write a brief report explaining how a water treatment facility
purifies water for drinking. Check out our interactive version
of the water