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Number of H and O atoms in 100grams of h20

User Will Lanni
by
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1 Answer

6 votes

Answer:

# O atoms =
3.3407325*10^(24)

# H atoms =
2(3.3407325*10^(24)) = 6.681465*10^(24)

Step-by-step explanation:

Stoichiometry

We're given:

  • 100 g of H2O
  • # H atoms?
  • # O atoms?

1) Find the moles of H2O.


n=(m)/(M) where n is moles, m is mass and M is molar mass


n=(100)/(2(1.01)+16.00)


n=(100)/(18.02)


n=5.54938956715\hspace{4}mol

2) Find the number of molecules of H2O.

n × Avogadro's number = # atoms


5.54938956715*6.02*10^(23)\\=3.3407325*10^(24)

∴ There are
3.3407325*10^(24) molecules of H2O.

3) Find the number of atoms of H and O.

There are 2 H atoms and 1 O atom in every molecule of H2O.

Therefore...

# O atoms =
3.3407325*10^(24)

# H atoms =
2(3.3407325*10^(24)) = 6.681465*10^(24)

User Gunnar Kiesel
by
8.2k points