Question
(a) How many degrees of freedom are there due to vibration motion of diatomic gas molecules?
(b) How many degrees of freedom are there for monoatomic, diatomic and triatomic gas due to translational and rotational motion only?
Solution
(a) The degree of freedom is one.
Reason: Diatomic gas molecule has at the maximum six degrees of freedom (2x3 = 6) out of which three are due to translational motion, two are due to rotational motion.
(b) Monoatomic gas molecule has only three degrees of freedom and they are only translational.
Diatomic gas molecule has five degrees of freedom.
Consider a triatomic linear gas molecule like CO2 which has seven degrees of freedom and triatomic angular has six degrees of freedom.
