Chemical Thermodynamics Question 40
Question: Equal volumes of monoatomic and diatomic gases at same initial temperature and pressure are mixed. The ratio of specific heats of the mixture $ (C_{p}/C_{v}) $ will be [AFMC 2002]
Options:
A) 1
B) 2
C) 1.67
D) 1.5
Show Answer
Answer:
Correct Answer: D
Solution:
$ C_{v}=\frac{3}{2}RT;C_{p}=\frac{5}{2}RT $ for monoatomic gas
$ C_{v}=\frac{5}{2}\text{RT;},C_{p}=\frac{7}{2}RT $ for diatomic gas
Thus for mixture of 1 mole each, $ C_{v}=\frac{\frac{3}{2}RT+\frac{5}{2}RT}{2} $ and $ C_{p}=\frac{\frac{5}{2}RT+\frac{7}{2}RT}{2} $
Therefore, $ C_{p}/C_{v}=\frac{3RT}{2RT}=1.5 $ .