Question

Energy of all molecules of a monoatomic gas having a volume V and pressure P $\frac{3}{2}$is . The total translational kinetic energy of all molecules of a diatomic gas as the same volume and pressure is

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

Energy of 1 mole of gas $\frac{f}{2}RT=\frac{f}{2}PV$ where f = Degree of freedom
Monoatomic or diatomic both gases posses equal degree of freedom for translational motion and that is equal to 3 i.e. f = 3 $\therefore$ $E=\frac{3}{2}$
Although total energy will be different, For monoatomic gas $E_{total}=\frac{3}{2}PV$ [As f = 3]
For diatomic gas $E_{total}=\frac{5}{2}PV$ [As f = 5]