No clue, Thermochemistry

1. Oct 20, 2007

ace123

1. For a certain reaction at constant pressure, delta U= -72 KJ, and 39KJ of expansion work is done by the system. What is delta H for this process.

2. I basically have no idea what to do because it's not in my textbook and my professor has never taught this. Maybe If I knew what the delta U stood for I could understand it.

Thanks

Edit: Wild guess, answer is -111 KJ?

Last edited: Oct 20, 2007
2. Oct 20, 2007

ace123

Anybody know what the damn delta U supposed to signify

3. Oct 20, 2007

Staff: Mentor

4. Oct 20, 2007

ace123

No, It does not. In my book this is the only way this is written $$\Delta{H}\,=\,\Delta{E}\,+\,P\Delta{V}$$ My guess was that it stood for E but i wasnt sure. Does that I am right?

5. Oct 20, 2007

eli64

yes, some places use U and some use E, they are the same

6. Oct 20, 2007

ace123

Okay, Thanks

Edit: Are you stalking my posts eli64 :rofl: