Question

Which of the following gas molecules have equal total kinetic energy and translational kinetic energy?

Answer 1

Correct option  (b) He

Explanation:

The total kinetic energy of a molecule is the sum of its translational, vibrational and rotational kinetic energies. The monatomic molecules do not possess vibrational and rotational kinetic energies. Hence, noble gases (like He, Ar etc.) fulfill the criteria.

Answer 2

Total kinetic energy = Translation KE+ Rotation and Vibrational KE, because the Vibrational energy has to small and also neglected.

Here the total Kinetic energy = Translation of KE plus Rotational KE for the molecules with the one atoms.

hope the Rotational KE becomes negligible and Kinetic energy is translation.

Then the answer is (2) He.

hope the student can get best answer.