105k views
2 votes
How many molecules of H20 are present in 7.30 g of water?

1 Answer

0 votes

Answer:

2.44×10²³ molecules

Step-by-step explanation:

From the question given above, the following data were obtained:

Mass of H₂O = 7.30 g

Number of molecules of H₂O =?

From Avogadro's hypothesis:

1 mole of H₂O = 6.02×10²³ molecules

1 mole of H₂O = (2×1) + 16

= 2 + 16

= 18 g

Thus,

18 g of H₂O = 6.02×10²³ molecules

Finally, we shall determine the number of molecules present in 7.3 g of H₂O. This can be obtained as follow:

From Avogadro's hypothesis:

18 g of H₂O = 6.02×10²³ molecules

Therefore,

7.3 g of H₂O = 7.3 × 6.02×10²³ / 18

7.3 g of H₂O = 2.44×10²³ molecules

Thus, 7.3 g of H₂O contains 2.44×10²³ molecules

User Imo
by
3.6k points