The PV diagram shows the compression of 44.1 moles of an ideal monoatomic gas from state A to state B. Calculate Q, the heat added to the gas in the process A to B. Data: PA= 1.90E+5 N/m^2 VA= 1.93E+0 m^3 PB= 1.31E+5 N/m^2 VB= 7.90E-1 m^3.
deltaE_int = Q-W
deltaE_int = (3/2)((PB)(VB)-(PA)(VA))
When plugging the given variables, I got deltaE_int = -394815 J
W = nRTln(Vf/Vi)
Vf is VB and Vi is VA
Substitute "T" as T = PV/nR
W = nR(PV/nR)ln(VB/VA)
= (PV)ln(VB/VA)
And apparently "P" will be the average value of pressure between points A and B so:
Pavg = (PA+PB)/2
= (1.90E+5 N/m^2 + 1.31E+5 N/m^2)/2
= 160500 N/m^2
Same thing for average volume:
Vavg = (VA+VB)/2
= 1.36 m^3
W = (Pavg)(Vavg)ln(VB/VA)
Q = deltaE_int + W
= 394815J + (Pavg)(Vavg)ln(VB/VA)
= -589791.9372 J
= -5.90E+5 J
But that is apparently wrong, though I don't know what I did wrong. Any help please would be appreciated!
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