Materials Required:
l 2.5 liter plastic jug
l Scissors
l Nail
l Hammer
l Pebbles, gravel, and sand (coarse and fine)
l Glass jar
l Muddy water
The help of one of your parents
Procedure:
- Cut off the bottom of a 2.5 liter plastic jug. Then, unscrew the cap and ask one of your parents to punch a few small holes in it with the tip of a nail and a hammer. Screw the cap back on and turn the jug upside down.
- Fill the jug with equal layers of pebbles, gravel, coarse sand, and fine sand. The pebbles go in first, the gravel next, then the coarse sand, and, finally, the fine sand on top. Don’t fill the jug completely; leave a couple of inches free.
- Hold the jug over a clear glass jar. If possible, prop up the jug so that it rests securely over the jar.
- Now, pour some muddy water onto the sand. In a few minutes, clean water will trickle into the jar.
This Is What Happens:
You have just performed filtration. Filtration is the removal of material that is suspended in a liquid. The muddy water contained many impurities, and these were trapped—filtered—by the layers in your jug. The water itself, however, was free to pass through the layers and into the jar. Of course, you shouldn’t drink this water because it is not really clean enough for drinking.
