Monday, 4 April 2016

thermodynamics - How to calculate the final temperature of a gas when it undergoes adiabatic expansion?


The question is as follows:



A sample of 4.0 moles of a gas (Cv,m=21 Jmol1K1) has an initial pressure of 304.4 kPa and an initial volume of 20 dm3 at 270 K. It undergoes an adiabatic expansion against a constant external pressure of 79.8 kPa, until the volume has increased by a factor of 3. Calculate the final temperature.




I have calculated: Q=0 and w=3192 J and change in internal energy =ΔU=31922 J.


The next question is to calculate the final temperature of the gas. However, I am unsure on how to calculate this. Originally I thought as Q=0, then the final temperature would be the same as the initial temperature. However, I have realized this is incorrect.




No comments:

Post a Comment

readings - Appending 内 to a company name is read ない or うち?

For example, if I say マイクロソフト内のパートナーシップは強いです, is the 内 here read as うち or ない? Answer 「内」 in the form: 「Proper Noun + 内」 is always read 「ない...