How many water molecules are present in 1.0 g of water?

Answer 1

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1.0 grams first needs to be converted into moles. Do this by dividing the 1.0 gram by the molecular mass of the water (18.0151 grams/mole).

The number moles multiplied by 6.023 * 10^23 (this is called Avogadro's number) will give the number of molecules.

1.0 grams / 18.0151 grams/mole = 0.0555 moles.

0.0555 moles * 6.023 * 10 ^23 molecules/mole = 0.334 * 10 ^23
= 3.34 * 10^22 molecules.