Bond Enthalpies

Moderators: Chem_Mod, Chem_Admin

Victoria Luu - 1C
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

Bond Enthalpies

Postby Victoria Luu - 1C » Tue Feb 05, 2019 9:51 pm

Why is it that the bonds formed will always have a negative sign? Is it because they are releasing heat after the bond is formed?

Posts: 70
Joined: Fri Sep 28, 2018 12:24 am

Re: Bond Enthalpies

Postby Danielle_Gallandt3I » Tue Feb 05, 2019 10:09 pm

Yes, that is correct. The bonds that form spontaneously release energy because the molecule formed is more stable (and therefore at a lower energy) than each of the elements separately. The molecule therefore releases energy by forming a bond, so q (or delta H) is negative

Posts: 34
Joined: Fri Sep 28, 2018 12:21 am

Re: Bond Enthalpies

Postby beckyolmedo1G » Tue Feb 05, 2019 10:11 pm

yes, I believe so. When bonds break, energy is required to break the bond so it is positive. However, when bonds are formed, energy is released that is why it is negative. So breaking a bond is endothermic while forming a bond is exothermic.

Return to “Concepts & Calculations Using First Law of Thermodynamics”

Who is online

Users browsing this forum: No registered users and 1 guest