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_{v}=(3/2)nR and is initially at a temperature T

_{0}, a pressure P

_{0}and a volume V

_{0}. The process a->b consists of a quasistatic, isobaric expansion to twice the initial volume. The process b->c consists of a quasistatic, isochoric decrease in pressure and the process c->a is a quasistatic , adiabatic compression.

(a) In terms of the initial pressure at point a, P

_{0}, what is the pressure at the point c?

Worked this out to be P

_{c}= 2

^{-ɣ}P

_{0}

(b) In terms of the initial temperature at point a, T

_{0}, what is the temperature at points b and c.

Worked these out to be T

_{b}= 2T

_{0}and T

_{c}= 4

^{-1/f}T

_{0}

(c) Construct a table which displays for each of the three processes in this cycle:

The work done, the heat transfer, the change in internal energy, the change in enthalpy and the change in entropy. Express your answers in terms of R, the universal gas constant, n, the number of moles of the gas present and T

_{0}, the initial temperature at point a.

For a->b:

Work done: W=-PΔV=-P

_{0}(2V

_{0}-V

_{0})=-P

_{0}V

_{0}=nRT

_{0}

Heat transfer: 0?

Change in internal energy: (f/2)nRΔT=(f/2)nR(T

_{b}-T

_{a})=(f/2)nR(2T

_{0}-T

_{0})

Change in enthalpy: ΔH=ΔU+PΔV=(f/2)nR(4

^{-1/f}T

_{0}-2T

_{0})+nRT

_{0}

Change in entropy: ΔS=nRln(V

_{f}/V

_{i})=nRln(2)

For b->c:

Work done: 0

Heat transfer: Does this = ΔU?

Change in internal energy: ΔU=(f/2)nRΔT=(f/2)nR(T

_{c}-T

_{b})=(f/2)nR(4

^{-1/f}T

_{0}-2T

_{0})

Change in enthalpy: ΔH=ΔU+ΔPV=(f/2)nR(4

^{-1/f}T

_{0}-2T

_{0})+0

Change in entropy: ΔS=nRln(V

_{f}/V

_{i}) Does this work here?

I'm just not sure if I'm on the right track... Especially for part (c). Any help with this would be appreciated.