We can arrange correctly the mean free paths of Hydrogen, Nitrogen, Oxygen. They well be in the following order at the same temperature :
`H_2, N_2 and O_2`
`H_2, O_2, N_2`
`O_2, H_2, N_2`
`N_2, O_2, H_2`
how we will arrange the atoms in the oder of mean free path