The average energy per molecule of a triatomic gas at room temperature T is

Question

The average energy per molecule of a triatomic gas at room temperature T is (A) 3kT (B) (1/2)kT (C) (3/2)kT (D) (5/2)kT

Tardigrade Admin · Accepted Answer

A triatomic (non-linear) gas molecule has

6

degrees of freedom (

3

translational,

3

rotational and no vibrational) at room temperature.
According to the law of equipartition of energy, the average energy per molecule of a triatomic gas at room temperature

T

is

\overset{ˉ}{E} = \frac{1}{2} f k T = \frac{1}{6} 6 k T = 3 k T

Q. The average energy per molecule of a triatomic gas at room temperature $T$ is

$3 k T$

$\frac{1}{2} k T$

$\frac{3}{2} k T$

$\frac{5}{2} k T$

Q. The average energy per molecule of a triatomic gas at room temperature T is

3kT

21​kT

23​kT

25​kT

A triatomic (non-linear) gas molecule has 6 degrees of freedom (3 translational, 3 rotational and no vibrational) at room temperature. According to the law of equipartition of energy, the average energy per molecule of a triatomic gas at room temperature T is Eˉ=21​fkT=61​6kT=3kT

Q. The average energy per molecule of a triatomic gas at room temperature $T$ is

$3 k T$

$\frac{1}{2} k T$

$\frac{3}{2} k T$

$\frac{5}{2} k T$