Quiz 1, #1

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manasa933
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Joined: Fri Sep 29, 2017 7:04 am

Quiz 1, #1

Postby manasa933 » Fri Feb 02, 2018 3:28 pm

On quiz 1, question 1, there was a question like "Do you expect there to be a difference in your answers in part 'a' and 'b'? Why?" What's the reason that there won't be a difference?

Cam Bear 2F
Posts: 60
Joined: Thu Jul 27, 2017 3:01 am

Re: Quiz 1, #1

Postby Cam Bear 2F » Fri Feb 02, 2018 3:45 pm

The question is comparing using bond enthalpies and standard enthalpies of formation to find the change in enthalpy of the reaction. In this case you would expect there to be a difference in the answers because bond enthalpies are averages from many different molecules. Therefore, that method will be the least accurate and slightly different from the answer the standard enthalpies of formation will give you.

Sarah Wax 1G
Posts: 29
Joined: Sat Jul 22, 2017 3:00 am

Re: Quiz 1, #1

Postby Sarah Wax 1G » Sun Feb 04, 2018 10:58 pm

Exactly. There's a difference because one of the methods (bond enthalpies) relies on only the average bond energies/enthalpies for a certain bond. However the other method (enthalpies of formation) are specific to that molecule and tell you the exact energy which is needed to form it.


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