Calculate the molecular diameter of helium from its van der Waals constant `b`. `(b=24cm^(3)mol^(-1))`

Explanation

Since `b=4xx` Volume occupied by the molecules in `1 mol` of a gas
or `b=4 N_(A)((4)/(3)pi r^(3))`
`:. R=((3b)/(16 N_(A)pi))^(1//3)`
`={(3xx24)/(16(6.023xx10^(23))(3.14))}^(1//3)`
`=1.335xx10^(-8)cm=133.5 Pm`
`:. D=2r=2xx133.5 Pm=267 Pm`