Are definitely monoatomic
Are definitely rigid diatomic
Are definitely non-rigid diatomic
Can be monoatomic or rigid diatomic
The correct option is D Can be monoatomic or rigid diatomic
The value of Cp is given as (f/2 + 1)R and that of Cv is given as (f/2)R
Hence the possible values of f for Cp or Cv to be 5/2R are 3, 5 respectively.
The degrees of freedom for a monoatomic gas is 3.
The degrees of freedom for a rigid diatomic gas is 5.
Hence correct answer is option D.