13.1 Estimate the fraction of molecular volume to the actual volume occupied by oxygen gas at STP. Take the diameter of an oxygen molecule to be 3 Å.
Radius of an oxygen molecule, r = d2=32=1.5 Å = 1.5 × 10−8cm
The actual volume occupied by 1 mole of oxygen gas at STP = 22400 cm3
Molecular volume of oxygen gas is given by, V=43πr3N
Where N is Avogadro’s number = 6.023 × 1023 molecules/mole
V=43×3.14×(1.5×10−8)3×6.023×1023=8.51 cm3
The ratio of the molecular volume to the actual volume of oxygen=8.5122400 = 3.8 × 10−4
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