Calculate the number of water molecule present in one drop of water wh

1.	Calculate the number of water molecule present in one drop of water which weighs 0.18 g.
Answer» The molecular mass of water (H₂O) is 18. 18 g of water molecule = 1 mole. 0. 18 g of water = \(\frac{1}{18}\) x 0.18 = 0.01 mole. 1 mole of water (Avogadro’s number) contains 6.023 × 10²³ water molecules. 0. 01 mole of water contain \(\frac{6.023\times10^{23}}{1}\) x 0.01 = 6.023 × 10²¹molecules.

Calculate the number of water molecule present in one drop of water which weighs 0.18 g.

Answer»

The molecular mass of water (H₂O) is 18.

18 g of water molecule = 1 mole.

0. 18 g of water = \(\frac{1}{18}\) x 0.18 = 0.01 mole.

1 mole of water (Avogadro’s number) contains 6.023 × 10²³ water molecules.

0. 01 mole of water contain \(\frac{6.023\times10^{23}}{1}\) x 0.01 = 6.023 × 10²¹molecules.