# Me again! (ideal gas/free expansion) need help soon

1. Dec 5, 2004

### don_anon25

Here's my problem:
An ideal gas is allowed to expand freely into an evacuated chamber.
The gas is at a pressure of 5 bar and a temperature of 45 degrees Celsius.
Find the final temperature and pressure of the gas.
Find the entropy produced.

W=0, Q=0, dU=0, and dT=0. So the final temp. is 45 degrees Celsius.
I need pressure at final state though...
dU=0 implies that u1=u2. But I don't know what the gas is, so I can't get values for these.

Am I missing something obvious?