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How many molecules are in 3.7 g H2O

User Arcticfox
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2 Answers

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Step-by-step explanation:

Find out number of molecules first. To find out number of molecules, first we need to know the number of moles present. The number of moles can be obtained by dividing the weight by molecular mass. The Molecular mass of water is 18. Now, by multiplying the moles with the Avogadro number we can find out the number of molecules. Avogadro number is 6×(10 to the power 23). Hence the final result is 3.7/18 ×6 × ( 10 to the power 23).

Hope this helps, if not I'm very sorry.

User Abhay Dwivedi
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7 votes
No. of molecules= (No. of moles)*NA

No. of moles= (Given mass)/GMM

Given mass= 3.7

GMM of H2O= 18

Hence,

No. of moles= 3.7/18

NA= 6.022*10^23

so,

No. of molecules= (3.7/18)*6.022*10^23
User Codded
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