Finding change in enthalpy when given bond enthalpies

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veneziaramirez 3I
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Joined: Fri Sep 29, 2017 7:07 am

Finding change in enthalpy when given bond enthalpies

Postby veneziaramirez 3I » Sat Jan 20, 2018 3:22 pm

Do we subtract the reactants from the products or do we add all the bond enthalpies together ?

Emma Ward 2C
Posts: 32
Joined: Fri Sep 29, 2017 7:05 am

Re: Finding change in enthalpy when given bond enthalpies

Postby Emma Ward 2C » Sat Jan 20, 2018 3:51 pm

When given bond enthalpies, it helps to draw the lewis structures and to analyze the change in the structures. When given bond enthalpies, you take the sum of the bonds broken minus the sum of the bonds formed! Hope this helps!

Helen Shi 1J
Posts: 78
Joined: Sat Jul 22, 2017 3:00 am

Re: Finding change in enthalpy when given bond enthalpies

Postby Helen Shi 1J » Sat Jan 20, 2018 8:42 pm

Could you also add up all the bond enthalpies for all bonds of the products minus all the bond enthalpies for the reactants to find the reaction enthalpy?

Anne 2L
Posts: 35
Joined: Fri Sep 29, 2017 7:05 am

Re: Finding change in enthalpy when given bond enthalpies

Postby Anne 2L » Sat Jan 20, 2018 9:17 pm

Yes, you can subtract all of the reactants from all of the products and still get the correct answer. Technically however the enthalpy of the reaction is the net of the energy released from forming bonds and the energy absorbed from breaking bonds.


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