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**1. Homework Statement**

1 mole of a monoatomic gas undergoes reversible expansion from 30 L and 400K to 60 L. The molar heat capacity in this situation is (3/2)R, independent of temperature. Calculate the final pressure and temperature of this process if it is adiabatic.

**2. Homework Equations**

Q= 0 if it is adiabatic

Q= nCv(dT)

PV=nRT

P1V1= P2V2

monoatomic Cv= (3/2)R <-- heat capacity at const. vol.

**3. The Attempt at a Solution**

Using Q=0, 0= nCv(dT)

0= (1 mol)(3/2)(R)(dT)

dT= 0

P1V1=nRT or (P1)(30L)=(1)(8.314 J/mol K)(400 K)

P1= 1.1 atm (using conversion factor)

Substituting into P1V1=P2V2, I get 0.55 atm.

Temperature is still 400 K at the end

I wanted to make sure if this was correct (the fact that the change in temp is zero while it was adiabatic confused me).

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