Which of the following has longest mean free path under identical conditions of temperature and pressure ?

Which of the following has longest mean free path under identical cond

1.	Which of the following has longest mean free path under identical conditions of temperature and pressure ?
Answer» `H_(2)` `N_(2)` `O_(2)` `CO_(2)` Solution :Mean FREE path (l) `(1)/(sqrt(2)pisigma^(2)n), i.e., l PROP (1)/(sigma^(2))` where `sigma`=MOLECULAR diameter Under identical conditions of T and P,n is same, As `sigma` is LOWER for `H_(2)`, l will be LARGEST.