Question

The degrees of freedom of Oxygen gas molecule at normal temperature is:

• A. $3$
• B. $5$
• C. $6$
• D. $4$

Answer 1

The correct option is B $5$

We know Oxygen gas has diatomic molecules.
A diatomic gas molecule has degrees of freedom due to the translations, rotations, and vibrations of the molecule. The center of mass motion of the entire molecule accounts for 3 translational degrees of freedom. In addition, the molecule has two rotational degrees of motion and one vibrational but At normal temp, vibration is not possible, So it does not account for degree of freedom. Hence, the total no of degrees of freedom is f = 3 translational +2 rotational = 5.