An `HCl` molecule has rolational, translational and vibrational motions. If the rms velocity is `bar(v)`, m is its mass and `k_(B)` is Boltzmann constant, then its temperature will be :

Options

A. `(m vec v^2)/(5k_B)`
B. `(m vec v ^2)/(3k_B)`
C. `(m vec v^2)/(7 k_B)`
D. `(m vec V^2)/(6 k_B)`

Answer

D

Explanation

H-Cl is diatomic molecule hence degree of freedom is
f=3 (translational)+2 (rotational)+1(vibration)=6 `" ":. (1)/(2)mbarV^(2)= (6)/(2)K_(B)T :. T= (mbarV^(2))/(6k_(B))`.