Thermodynamics Question 330
The degrees of freedom per molecule of an ideal gas is 3. Work done by the gas is 100 J when it expands isobarically. The heat absorbed by the gas will be
Options:
A) 250 J
B) 150 J
C) 350 J
D) 200 J
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Degrees of freedom is 5
Hence $ C _{V}=\frac{3}{2}RT $ and $ C _{P}=\frac{5}{2}RT $
$ \frac{dQ}{dU}=\frac{nC _{P}dT}{nC _{V}dT}=\frac{C _{P}}{C _{V}} $
or $ \frac{dQ}{dQ-dW}=\frac{5}{7} $
$ \therefore $ $ dQ=3.5dW=350 $
$ = 350\ \text{J}$
BETA
