Calculate work for following process beginning with gas sample in a piston assembly with T=305K, P=1.79 atm, and V=4.29 L
a.) Irreversible expansion against a constant external pressure of 1 atm to a final volume of 6.52 L
I was able to calculate process a, -226 J but for
b.) Isothermal, reversible expansion to a final volume of 6.52L
I tried using the equation w= -nRT ln(V2/V1) but I did not end up with the correct number. Would I assume that I am dealing with one mole?
HW problem 4B. 13
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Re: HW problem 4B. 13
Because PV=nRT, you can calculate the amount of moles by plugging in the given information into the equation n=PV/RT. Using the value you found for n, you should be able to use the w=-nRTln(V1/V2) formula.
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Re: HW problem 4B. 13
We use the second equation when the external pressure is not constant, so in any reversible process
Re: HW problem 4B. 13
I am plugging the values into the w = -nRTln(V2/V1) equation but am not getting the right answer. Are my values correct?
n = (1.79atm)(6.52L)/(8.3145)(305K) = 0.00460 mol
w = -(.00460)(8.3145)(305)ln(6.52/4.29) = -488J
The answer in the book is -326J
n = (1.79atm)(6.52L)/(8.3145)(305K) = 0.00460 mol
w = -(.00460)(8.3145)(305)ln(6.52/4.29) = -488J
The answer in the book is -326J
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