1. Aim: To demonstrate how filtration can be used to remove solid particles from muddy water.
2. Requirements: a plastic bottle, a clean piece of cloth, powdered coal, fine sand, coarse sand, muddy water containing rubbish, scissors or a cutter (to cut the base of the bottle).
3. Procedure:
- Cut off the base of the plastic bottle. Tie a clean piece of cloth tightly over the bottle’s mouth.
- Hold the bottle upside down and pour powdered coal into it to form the first layer. Then, add fine sand for the second layer and finally, coarse sand for the top layer, creating three layers inside the bottle.
- Place the bottle, cut-side down, on its lower base as shown in the diagram.
- Slowly pour the muddy water containing rubbish into the bottle and observe the water as it passes through the layers.
- Observe: The water that flows out of the bottom will appear cleaner, though it may still contain microorganisms.
4. Conclusion: The layers of coal, fine sand, and coarse sand act as a basic filter to remove visible solid particles from the muddy water, making it appear cleaner. However, microorganisms may still be present, so additional purification methods are needed for safe drinking water.
