Moderators: Chem_Mod, Chem_Admin

Nhan Nguyen 2F
Posts: 52
Joined: Thu Jul 13, 2017 3:00 am
Been upvoted: 1 time

HW Q.8.49

Postby Nhan Nguyen 2F » Fri Jan 19, 2018 12:37 am

Can someone explain to me why we use PV=nRT for this problem? I'm just a little confused on when we can use the ideal gas law. Thank you

Lisa Tang 1C
Posts: 62
Joined: Fri Sep 29, 2017 7:05 am
Been upvoted: 2 times

Re: HW Q.8.49

Postby Lisa Tang 1C » Fri Jan 19, 2018 9:28 am

You use PV=nRT for this problem because of the equation on page 290 of the textbook.
delta H = delta U + delta ngasRT where delta ngas=the final number of moles of gas-the initial number of moles of gas. The problem gives you a delta H value you can plug in, and with that, you are able to use PV=nRT/the ideal gas law to relate delta H and delta U.
Hope that helps!

Posts: 19201
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 837 times

Re: HW Q.8.49  [ENDORSED]

Postby Chem_Mod » Fri Jan 19, 2018 10:09 am

Great answer.

I will do a similar example in class today.

Return to “Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)”

Who is online

Users browsing this forum: Anh Trinh 1J, Megan Singer 3D and 4 guests