Chemical Thermodynamics Question 411
Question: An ideal gas occuping a volume of $ 2dm^{3} $ and a pressure of 5 bar undergoes isothermal and irreversible expansion against external pressure of 1 bar. The final volume of the system and the work involved in the process is
Options:
A) $ 10dm^{3},1000J $
B) $ 8dm^{3},-800J $
C) $ 10dm^{3},-800J $
D) $ 10dm^{3},-1000J $
Show Answer
Answer:
Correct Answer: C
Solution:
- $ P_1V_1=P_2V_2 $
$ \therefore V=\frac{5bar\times 2dm^{3}}{1bar}=10dm^{3} $ Work, $ W=-P_{ext}(V_{final}-V_{initioal}) $
$ =-1,bar( 10-2 ) $
$ =-1\times 10^{5}Pa\times 8\times {{10}^{-3}}m^{3} $
$ =-800J $