A sample of water has a mass of 10.0 grams.What is the number of molecules of water in the 10.0 gram sample (H = 1u,O = 16u)? A) 1.99 $\times$ 10²³ B) 2.00 $\times$ 10²³ C) 2.56 $\times$ 10²³ D) 3.34 $\times$ 10²³ E) 4.25 $\times$ 10²³

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Quizplus · Accepted Answer

The molar mass of water (H₂O) is 18 g/mol. Therefore, 10.0 grams of water is 10.0/18 moles. Using Avogadro's number (6.022 * 10²³ molecules/mol), the number of molecules is (10.0/18) * 6.022 * 10²³ ≈ 3.34 * 10²³ molecules.

A Sample of Water Has a Mass of 10 ×\times× 1023 B) 2

A Sample of Water Has a Mass of 10 $\times$ 10²³
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