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It covers two-thirds of the Earth's surface and makes up about 60% of adult's bodies, including 75% of our brains! Each day we need to consume more than two liters of the stuff—through liquids we drink and foods we eat. Although there's plenty of H2O around, much of it is either inaccessible or inconsumable to humans. But with water treatment, we're able to purify water and get what we need.
CAUTION: Adult supervision required when handling chemicals and/or cutting objects. Remember to use proper safety equipment when experimenting.
Because we won't disinfect our water, it is NOT safe to drink.
There are five steps to basic water purification: aeration, coagulation, sedimentation, filtration, and disinfection. Our project took us through the first four. Aeration adds air to the water. It allows gases trapped in the water to escape and adds oxygen to the water. Coagulation is the process which allows dirt and other suspended solid particles to chemically 'stick together'? into floc (clumps of alum and sediment). During this step, the water is also clarified, or made clear and colorless. Sedimentation is the process that occurs when gravity pulls the particles of floc to the bottom of the container. So as the water sits undisturbed, most of the floc settles, preparing the water for the next step. Filtration is the process where remaining solid particles and floc are separated and removed from the from the water. Disinfection is the final step, in which water is chemically treated to remove bacteria and other micro-organisms. These unseen bacteria can cause severe sickness and even death in humans.
Because we didn't disinfect our water, it is NOT safe to drink.