Question

For a gas $\frac{R}{C_{v}}=0.4,$ where $R$ is the universal gas constant and $C_{v}$ is the molar specific heat at constant volume. The gas is made up of molecules which are

• A. rigid diatomic
• B. monoatomic
• C. non- rigid diatomic
• D. polyatomic

Answer 1

Answer: (A)

$\frac{R}{C_{v}}=0.4 \Rightarrow \frac{C_{p}-C_{v}}{C_{v}}=0.4$
$\frac{c_{p}}{c_{v}}-1=0.4$
$\therefore \frac{C_{p}}{C_{v}}=1.4 \Rightarrow \gamma=1.4$
As $\gamma=1.4$, the gas is diatomic in nature. Example, air molecules.