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How to calculate the number of molecules in 18g of H2O

User Tai Tran
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1 Answer

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We, know molecular mass of water is, M = 16 g/mol .

Given mass of water, m = 18 g.

We know, number of moles is given by :


n = (18\ g)/(16 \ g/mol)\\\\n = 1.125\ moles

Now, 1 mole of any compound contains 6.022 × 10²³ molecules.

So, number of moles in 1.125 moles of water is 1.125 × 6.022 × 10²³ =

6.77 × 10²³ molecules.

Hence, this is the required solution.

User Mark Lenser
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