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Four moles of an ideal gas originally at 323 oC and 7.3 atm underwent a complete expansion against a constant external pressure of 1 atm and did 8kJ of work. Calculate q, ΔE, ΔH.
Solve for the missing initial variable (Vi):
hint: rearrange PV=nRT to do this!
Solve for Vf:
Hint: We can use Vi and the work to find Vf
In the work equation, recall P must be in Pa!
We now have three of four final variables. We can solve for Tf
With the initial and final temperatures we can find ΔH and ΔU
Recall: Cp= 5/2(R)
Cv=3/2(R) You should know this for your exam!