Consider one mole of oxygen gas at STP. It occupies 22.4 litre of volume which will contain 6.023 × 1023. (ie. Avogadro number) molecules. Considering spherical shape of molecule, volume of oxygen molecule
Volume of 6.023 × 1023 molecules
= 4/3 × 3.142(1.5)3 × 10-30 × 6.02 × 1023 m3
= 85.1 × 10-7m3
= 8.51 × 10-6m3 = 8.51 × 10-3
litre Molecular volume of one mole of oxygen (∵ 1m3 = 103 litre)
∴ Molecular volume of one mole of oxygen = 8.51 × 10-3 litre
Actual volume occupied by one mole of oxygen at STP = 22.4 litre
Fraction of molecular volume to actual volume
