Kinetic Theory Of Gases Question 90
Question: The ratio $ C _{p}/C _{v} $ for a gas mixture consisting of 8g of helium and 16 g of oxygen is
Options:
A) 24.2/15
B) 15/23
C) 27/17
D) 17/27
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ \gamma $ for $ He=5/3; $
$ \gamma $ for $ ~O _{2}=7/5 $ 8 g of He is equal to 2 moles of He and 16 g of $ ~O _{2}=\frac{1}{2}mole $ of $ ~O _{2}=7/5 $ gas. Total one has $ 2{\scriptstyle{}^{1}/{} _{2}} $ moles.
$ \
Therefore $ The weighted average is $ =( 2\times \frac{5}{3}+\frac{7}{5}\times \frac{1}{2} )\times \frac{2}{5}={ \frac{10}{3}+\frac{7}{10} }\times \frac{2}{5} $
$ =\frac{121}{30}\times \frac{2}{5}=\frac{24.5}{15} $
BETA
