Purifying water
10 minutesHere in the Netherlands, all we have to do is turn on the tap to drink clean water. This is not as simple as it seems: it takes a lot of work to make water clean enough to drink. Why don’t you give it a try?
Requirements
Steps
Put the funnel on top of the glass and put the coffee filter and a piece of kitchen paper inside it.
Scoop two tablespoons of charcoal powder into the filter. That is your first layer. Next, scoop two tablespoons of sand into the filter. That is the second layer. Do not mix the layers together.
Pour the dirty water onto the sand.
Tip: Pour the water slowly, so that it flows gently through the layers in the filter without mixing them.
Look at the colour of the filtered water in the glass. Is it clear? If not, repeat the steps.
What did you discover
When the water is clear, you have purified dirty water yourself, using sand and charcoal. The dirt in the water sticks to the grains of charcoal and sand, and stays behind in the filter.
Warning: This water still is not safe to drink! Although the filtered water looks clean, it may still contain contaminants that you cannot see with the naked eye. The water in the glass is not as clean as tap water.
Water treatment plants work in the same way, but use more steps and operate on a much larger scale. They use sand filters and other techniques to purify our drinking water. Thanks to these techniques, everyone in the Netherlands can drink clean water from the tap every day.