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### Equations for 8.27

Posted: Sat Jan 23, 2016 8:40 pm
For this problem, it breaks up the two processes into irreversible and isothermic reactions. Which formulas am I supposed to use for each of them?

### Re: Equations for 8.27

Posted: Sat Jan 23, 2016 9:10 pm
For part (a) it says there is an irreversible expansion against a constant external pressure. So you use w=-Pexternal$\Delta$V.

For part (b) it talks about an isothermal, reversible expansion.

You would use the work equation w=-nRTln(vf/vi). But in order to find how many moles there are, you would use the ideal Gas law PV=nRT and solve for n. Then from there you just plug and chug.

Hope this helps!