Question

Volume occupied by one molecule of water when density=1g cm-3

Answer 1

The number of moles in 1 litre = 1000 / 18.02 = 55.5 moles. 1 mole of water = 6.022 x 10^23 molecules of water, So 55.5 moles of water = 55.5 x 6.022 x 10^23 = 3.34 x 10^25 molecules of water. The gram molecular mass of water is 18.02. Thus volume occupied by 1 H2O molecule is 2.99 ×10-23 ml.