Thermo: Need help finding T2 and V2 in an adiabat

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The discussion revolves around calculating various thermodynamic properties of an ideal gas undergoing adiabatic and reversible compression. The initial conditions include 1 mole of gas at 294 K and a pressure change from 0.83 atm to 10.0 atm. The user successfully calculated the initial volume (V1 = 29.1 L) but is uncertain about finding the final volume (V2) and temperature (T2). The key to solving the problem lies in applying the adiabatic condition, PV^γ = constant, which allows for the determination of V2 using the initial conditions. The conversation emphasizes the importance of recognizing that the constant K remains unchanged during the process.
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Homework Statement



1 mole of ideal gas initially at 294 K is compressed adiabatically and
reversibly from 0.83 atm to 10.0 atm. Calculate the initial and …final volumes,
the final temperature, \DeltaU; \DeltaH; Q; and W: Assume that Cv = (5/2)R

Given:

n = 1 mol
T1 = 294 K
P1 = 0.83 atm
P2 = 10 atm
Q = 0

Find
V1, V2, \DeltaU, Q, \DeltaH, T2, W

Homework Equations



1. The professor gave that specific heat at constant volume is (5/2)R, however, the volume of the problem changes. Is this equation completely irrelevant to the problem?

2. How to you find the final temperature and final volume?


The Attempt at a Solution



I started off with PV = nRT for the initial givens and obtained that V1 = 29.1 L

Now, I'm stuck. I've tried using the ideal gas equation again, but I have 2 unknowns. I tried rearranging the equation and setting it equal the initial equations. I know how to find the other unknowns, but I'm stuck at this part for some reason.
 
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Courtknee said:

Homework Statement



1 mole of ideal gas initially at 294 K is compressed adiabatically and
reversibly from 0.83 atm to 10.0 atm. Calculate the initial and …final volumes,
the final temperature, \DeltaU; \DeltaH; Q; and W: Assume that Cv = (5/2)R

Given:

n = 1 mol
T1 = 294 K
P1 = 0.83 atm
P2 = 10 atm
Q = 0

Find
V1, V2, \DeltaU, Q, \DeltaH, T2, W

Homework Equations



1. The professor gave that specific heat at constant volume is (5/2)R, however, the volume of the problem changes. Is this equation completely irrelevant to the problem?

2. How to you find the final temperature and final volume?

The Attempt at a Solution



I started off with PV = nRT for the initial givens and obtained that V1 = 29.1 L

Now, I'm stuck. I've tried using the ideal gas equation again, but I have 2 unknowns. I tried rearranging the equation and setting it equal the initial equations. I know how to find the other unknowns, but I'm stuck at this part for some reason.
You need to use the adiabatic condition: PV^\gamma = constant = K which can be rewritten: TV^{\gamma-1} = K/nR = constant

AM
 
I'm assuming that the constant K will remain the same for p1*v1 and p2*v2

If I set P1V1γ = K, then I can use that constant for P2V2γ and obtain the volume, correct?
 
Courtknee said:
I'm assuming that the constant K will remain the same for p1*v1 and p2*v2
If it didn't, it would not be constant!

If I set P1V1γ = K, then I can use that constant for P2V2γ and obtain the volume, correct?
Exactly.

AM
 
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