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https://www.jiskha.com/questions/1844015/a-single-water-molecule-has-a-given-mass-of-about-2-992-x-10-23-g-18-02-amu-estimate
A water molecule has a mass of 2.99 x 10^ -23 g. What is the number of molecules of water in 18.01 g of water?
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