Question:
Match the $C_{P} / C_{V}$ ratio for ideal gases with different tune of molecules.
Correct Option: 1
Solution:
$\gamma=\frac{\mathrm{C}_{\mathrm{p}}}{\mathrm{C}_{\mathrm{v}}}=1+\frac{2}{\mathrm{f}}$
where ' $f$ ' is degree of freedom
(A) Monoatomic $\mathrm{f}=3, \gamma=1+\frac{2}{3}=\frac{5}{3}$
(B) Diatomic rigid molecules,
$f=5, \gamma=1+\frac{2}{3}=\frac{7}{5}$
(C) Diatomic non-rigid molecules
$\mathrm{f}=7, \gamma=1+\frac{2}{7}=\frac{9}{7}$
(D) Triatomic rigid molecules
$f=6, \gamma=1+\frac{2}{6}=\frac{4}{3}$