Find the final internal energy of a gas.

[thatguythere]

Homework Statement

A thermally isolated container is filled with 2.3 mol of an ideal gas at T = 0°C.The gas is then compressed from 1.9 m3 to 0.3 m3. What is the final internal energy U of the gas? (Assume the process occurs at constant pressure.)

Homework Equations

U=3/2nRT
U=Q+W
W=pΔV
pV=nRT

The Attempt at a Solution

Q=0, so U=W

p(1.9)=(2.3)(8.314)(273.15)
p(1.9)=5223.2
p=2749.1

W=pΔV
=(2749.1)(0.3-1.9)
=(2749.1)(-1.6)
=-4398.6

The actual answer is 1.24kJ.

I attempted this as well just to see.

U=3/2nRT
=3/2(2.3)(8.314)(273.15)
=7834.8

Clearly I am lost. Any help would be greatly appreciated.

 

[thatguythere]

Nevermind. I got it :D