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Quiz 1, #1

Posted: Fri Feb 02, 2018 3:28 pm
by manasa933
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?

Re: Quiz 1, #1

Posted: Fri Feb 02, 2018 3:45 pm
by Cam Bear 2F
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.

Re: Quiz 1, #1

Posted: Sun Feb 04, 2018 10:58 pm
by Sarah Wax 1G
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.