(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The figure(Figure 1) shows a thermodynamic process followed by 150 mg of helium. Determine the pressure (in atm) at points 1, 2, and 3. Determine the temperature (in °C) at points 1, 2, and 3.

http://imgur.com/B7lwQ

n=.0375 mol

P_{1}=3 atm

P_{2}=1 atm

T_{1}=971.85 k

T_{2}=971.85 k

V_{1}=1000 cm^3

V_{2}=V_{3}=3000 cm^3

2. Relevant equations

PV=nRT

3. The attempt at a solution

I'm only on the pressure part right now. From the given chart P_{1}=3 atm. I used PV=nRT, and got that T_{1}and T_{2}are 971.85 K. With that, I used ideal gas law again to get that P_{2}=1 atm. However, I don't know how to get the pressure at point 3 since I don't know the temperature at that point. It looks like it goes through an isobaric compression from the isotherm to the adiabat to me. Any help is appreciated.

(303000)(.001)=(.0375)(8.314)T, T_{1}=T_{2}=971.85 K

P(.003)=(.0375)(8.314)(971.85), P_{2}=1 atm

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# Homework Help: Isobaric compression from isotherm to adiabat

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