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

An ideal monatomic gas is taken through the above cycle where p1= 2 X 105 Pa and V1 = 5 cm3. During the cycle both the pressure and volume will change such that p2 = 2 p1 and V2 = 4 V1.

a) How much work is done by the gas in going from state a to state c along path abc?

Wabc = 3 J

OK

b) What is the change in internal energy in going from b to c?

Ubc= J

c) What is the change in internal energy during the complete cycle?

UTOT = 0 J

OK

d) What is the change in entropy per mole of gas in going from b to c?

ΔSbc = J/K

e) What is the change in entropy per mole during the complete cycle?

ΔSTOT= 0 J/K

OK

I am having problems with Parts B and D.

2. Relevant equations

PV=NRT

Q = nCvdt

3. The attempt at a solution

I only have P and V. I cannot use the Ideal Gas Law to calculate n or T because I have two unknowns. I cannot use my Heat Equations because I am still missing n and T. I'm just stuck. If I can calculate B, I think I can get D...I just don't see any way to calculate the Heat in part B. HELP!

Thanks.

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# Homework Help: Energy and Entropy from P-V Diagram

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