The U.S. Public Health Service recommends the fluoridation
Chapter 16, Problem 76(choose chapter or problem)
The U.S. Public Health Service recommends the fluoridation of water as a means for preventing tooth decay. The recommended concentration is 1 mg F per liter. The presence of calcium ions in hard water can precipitate the added fluoride. What is the maximum molarity of calcium ions in hard water if the fluoride concentration is at the USPHS recommended level? (Ksp for CaF2 4.0 1011)
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