Convert 6.42 moles of H20 to molecules

3.86x10^24 molecules

Explanation:

From Avogadro's hypothesis, we understood that 1mole of any substance contains 6.02x10^23 molecules.

This means that 1mole of H2O contains 6.02x10^23 molecules.

Therefore, 6.42 moles of H20 will contain = 6.42 x 6.02x10^23 = 3.86x10^24 molecules

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