Question

A polyatomic ideal gas has $24$ vibrational modes. What is the value of $\gamma$ ?

• A. $1.03$
• B. $1.30$
• C. $1.37$
• D. $10.3$

Answer 1

Answer: (A)

Since each vibrational mode has $2$ degrees of freedom hence total vibrational degrees of
freedom $=48$
$f=3+3+48=54$
$\gamma =1+\frac{2}{f}=\frac{28}{27}=1.03$