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Science » Other Science

Cleaning Water

is a lesson in which students (Grades 3-5) create and test a system to filter "gray" water. Astronauts on the International Space Station (ISS) recycle their water, including moisture from their sweat and exhalations and water from showering and shaving. These wastewaters are purified and then used as drinking water. (National Aeronautics and Space Administration)

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Interesting Fact:

Public water systems have to meet a pH level of 6.5 to 8.5. The ISS water is required to be within the range of 6.0 to 8.5. The recycled water on the ISS is sterile, and there is no odor or bad taste.
The pH scale ranges from 0 to 14 and is a tool used by scientists to measure the strength of an acid or base.

pH color chart

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