Bond enthalpies

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Maggie Doan 1I
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Joined: Fri Sep 28, 2018 12:24 am

Bond enthalpies

Postby Maggie Doan 1I » Mon Feb 11, 2019 12:02 am

To solve for bond enthalpies, do we have to know the lewis structure of the molecules?

MichelleTran 1I
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Joined: Fri Sep 28, 2018 12:23 am

Re: Bond enthalpies

Postby MichelleTran 1I » Mon Feb 11, 2019 12:08 am

I think knowing them will be helpful, but the BDE would probably be given on the test/in a table maybe? That's how it's been for the examples we worked on in class and such.

Elizabeth Kim 4E
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Joined: Fri Sep 28, 2018 12:29 am

Re: Bond enthalpies

Postby Elizabeth Kim 4E » Mon Feb 11, 2019 12:03 pm

You don't need to know the lewis structures for the midterm, but my TA said it was easier to visualize if you drew out the Lewis structure

Cole Elsner 2J
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Joined: Fri Sep 28, 2018 12:25 am

Re: Bond enthalpies

Postby Cole Elsner 2J » Mon Feb 11, 2019 12:31 pm

Lewis structures ARE helpful for figuring out exactly what is being broken, but it is still possible to solve these problems just by looking at the differences between the reactants and products side.

Casandra
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Joined: Fri Sep 28, 2018 12:17 am

Re: Bond enthalpies

Postby Casandra » Mon Feb 11, 2019 2:06 pm

knowing the Lewis structure is helpful but the bond dissociation energies will be given which will also help you figure out how the bonds are formed or broken.

Aidan Ryan 1B
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Re: Bond enthalpies

Postby Aidan Ryan 1B » Mon Feb 11, 2019 2:07 pm

This equation is BE of reactants- BE of products right?

105085381
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Re: Bond enthalpies

Postby 105085381 » Mon Feb 11, 2019 2:31 pm

Will the bond dissociation energies definitely be given?

Fanny Lee 2K
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Joined: Fri Sep 28, 2018 12:29 am

Re: Bond enthalpies

Postby Fanny Lee 2K » Mon Feb 11, 2019 2:35 pm

105085381 wrote:Will the bond dissociation energies definitely be given?

The bond dissociation energies will definitely be given but they are given in positive values assuming bonds are broken. Be sure to be careful with the signs when applying it in the midterm and final.

PranitKumaran1F
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Joined: Thu Nov 08, 2018 12:17 am

Re: Bond enthalpies

Postby PranitKumaran1F » Mon Feb 11, 2019 3:59 pm

Knowing the Lewis structure would make it easier because then you would only need the calculate the specific bonds that are broken and formed, but if you don't know the Lewis structure you can still calculate bond enthalpies by calculating with all the bonds being formed and broken as well.

Nicklas_Wright_1A
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Joined: Fri Sep 28, 2018 12:23 am

Re: Bond enthalpies

Postby Nicklas_Wright_1A » Mon Feb 11, 2019 4:37 pm

You need to know the Lewis structure. Otherwise, you won't know how many bonds of each type there are.

Jordan Lo 2A
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Re: Bond enthalpies

Postby Jordan Lo 2A » Mon Feb 11, 2019 4:44 pm

I would know the Lewis structure just in case it isn't obvious what kind of bonds are being broken and formed, especially if there is a lot of change between products and reactants


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