SUMMARY:With the help of building filters we can learn about the basic knowledge of filters

Step 1: Materials

1-liter soda bottles cut in half

Napkins or paper towels

Gravel

Sand

Potable Aqua Chlorine Dioxide, water purification drops or tablets

Cups or scoops (for gravel and sand)

Activated Filter Carbon (available at pet stores)

Large water container for dirty water (pitchers or gallon jugs)

Dirty water (made by adding dirt, twigs, leaves, etc., to water)

Large waste container (plastic container or thick garbage bag for used filtering materials)

2 clean pitchers for clear water

Step 2: Procedure

Preparation

Pre cut enough 1-liter soda bottles for each student or for each group of students

Create dirty water

Set up spots for scooping in the filter materials (charcoal, sand, gravel, etc.)

There should be a little hole in the bottle cap so that water can pass

Procedure

1.Once you have made their filters, put the filter on a stable surface and pour in the dirty water.

2.You would observe that water is coming down in the second half of soda bottle and the water is clean.

3.When the whole clean water is drained remove the above part of soda bottle .

Gravel and sand remove large and small particles, carbon removes pesticides, chlorine and other chemicals and improves the taste of water.