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Name: Amber
Status: Student
Grade: 6-8
Location: GA
Country: United States
Date: November 2006

Can you please explain to me how hard water is formed and how to know that hard water has been created.

"Hard" water means the amount of calcium (Ca[+2]} and magnesium (Mg[+2]) present in the water. The amount of these ions depends upon the solubility of various calcium and magnesium minerals present in the ground from which the water is tapped. Rain water, which is not exposed to any minerals contains little or no calcium or magnesium and so is very "soft". The terms "hard" and "soft" are used for historical reasons and do not have anything to do with the usual meaning of the words "hard" and "soft".

Vince Calder

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