Bond Enthalpies

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Gisselle Cervantes 2G
Posts: 17
Joined: Wed Sep 21, 2016 2:58 pm

Bond Enthalpies

Postby Gisselle Cervantes 2G » Wed Feb 01, 2017 6:04 pm

In a bond enthalpy problem, when you determine which bonds are being broken and which ones are being formed, how do you calculate the delta H of the reaction? Is it the sum of delta H products minus the sum of delta H reactants or do you simply add the sum of the bonds broken and the sum of the bonds formed?

Amber Duong 1B
Posts: 10
Joined: Wed Sep 21, 2016 2:55 pm

Re: Bond Enthalpies

Postby Amber Duong 1B » Wed Feb 01, 2017 6:27 pm

To calculate enthalpy change of a reaction using bond enthalpies, you can add up either the bond enthalpies of the bonds broken and bonds made OR the bond enthalpies of the reactants and the products. It equates to the same enthalpy change.

Sangita_Sub_3H
Posts: 23
Joined: Sat Jul 09, 2016 3:00 am

Re: Bond Enthalpies

Postby Sangita_Sub_3H » Thu Feb 02, 2017 2:03 am

In addition, when bonds are formed, the bond enthalpies are negative, and when the bonds are broken, the bond enthalpies are positive. So, you can then just add up the new bonds formed and broken.


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