Finding Final Volume - almost got it

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    Final Volume
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The discussion focuses on calculating the final volume (Vf) of a gas given specific parameters, including initial conditions and energy transferred. The initial calculations yield a final temperature (Tf) of 449.7K and a final volume (Vf) of 17.28L. However, the teacher suggests the correct final volume should be 7.52L, indicating a possible misunderstanding of the formulas used. It is clarified that the constant pressure value provided is actually the specific heat capacity, not the pressure itself, which may have led to the incorrect application of the equations. Properly identifying and using the correct formulas is essential for accurate results.
sisigsarap
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Ok, here is what is given:

1.00 mol O2
Ti = 300K
Vi = 5.00L
4400 j of energy transferred by heat to the system
Vf = ?
Constant Pressure = 29.4 J/mol * K

So I set the problem up using Q = n(Constant Pressure)(Tf - T-i)
Solving for Tf I find that Tf is equal to 449.7K.

Then using equation (Vf - Vi) = (nR(Tf - Ti)) / P

Vf = ((1.00mol * 8.31 J/mol*K * 149.7K) / (1.013*10^5 N/m^2)) + 5.00L

I am getting Vf = 17.28 L

Can anyone tell me what I am doing wrong? My teacher told me the answer should be 7.52, could he of possibly meant 17.52?

Any help would be appreciated!
 
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1.The teacher is right.
2.The final temperature u computed is right...

3.The formula u used is wrong...

Daniel.
 
sisigsarap said:
Constant Pressure = 29.4 J/mol * K

This is the specific heat capacity, not pressure.
 
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