Question

How many water molecules are present in 11.2 litres of water?

Answer 1

1 mole is equal to 22.4 litres at NTP. And 1 mole have 6.23×10^23 atoms or for methane we can say 6.23×10^23 molecules. So 11.2 liters of methane contain 3.115×10^23 molecules of methane.

Answer 2

1 mole of water contains Avogadro number of water molecules which occupy 22.4 litres of volume at STP.

11.2 litres of water indicates 0.5 moles of water.

Number of water molecules in 0.5 moles of water = 0.5 x Avogadro number

= 0.5 x 6 x 10²³

= 3 x 10²³ molecules

Thus, In 11.2 litres of water, 3 x 10²³ molecules of water are present.

Hope it helps!!