One mole of an ideal gas at STP occupies 22.4 L. What is the ratio of molar volume to atomic volume of a mole of hydrogen? Why is the ratio so large? Take size of hydrogen molecule to be 1 Å.

Explanation

Å = `10^(-10)` m
Atomic volume of 1 mole of hydrogen
= Avogadro.s number `xx` volume of hydrogen molecule
`= 6.023 xx 10^(23) xx 4/3 xx pi xx (10^(-10) m)^(3)`
= 25.2 `xx 10^(-7) m^(3)`
Molar volume = `22.4 L = 22.4 xx 10^(-3) m^(3)`
`("Molar volume")/("Atomic volume") = 0.89 xx 10^(4) ~~ 10^(4)`
This ratio is large because actual size of gas molecule is negligible in comparison to the inter molecular separation.