4D.2 Textbook Question

Moderators: Chem_Mod, Chem_Admin

DHavo_1E
Posts: 118
Joined: Sat Aug 17, 2019 12:17 am

4D.2 Textbook Question

Postby DHavo_1E » Sun Feb 09, 2020 1:42 pm

Hello,

For the equation:
(delta enthalpy) = (delta internal energy) + (delta n)(RT),
What does it mean when the textbook says that delta enthalpy is more positive than delta internal energy for reactions that generate more gases? I don’t understand the link between this conclusion and their explanation explaining how less energy is obtained as heat at constant pressure than constant volume. Thank you!

DarrenKim_1H
Posts: 123
Joined: Fri Sep 20, 2019 12:17 am
Been upvoted: 1 time

Re: 4D.2 Textbook Question

Postby DarrenKim_1H » Sun Feb 09, 2020 5:41 pm

more gas implies a volume expansion, aka an increase of delta V, which according to PV = nRT, means there's an increase in the second part of the equations enthalpy = internal energy + nRT


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

Who is online

Users browsing this forum: No registered users and 1 guest