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 × 1021 molecules.