Why Bond Enthalpies are the least accurate

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Julia Go 2L
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Joined: Sun Sep 30, 2018 12:17 am
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Why Bond Enthalpies are the least accurate

Postby Julia Go 2L » Sun Feb 03, 2019 1:25 pm

I remember in lecture that Dr. Lavelle said that out of the three methods, using bond enthalpy to calculate ΔH is the least accurate. Can someone explain why this is?

Xuan Kuang 2L
Posts: 31
Joined: Wed Nov 14, 2018 12:23 am

Re: Why Bond Enthalpies are the least accurate

Postby Xuan Kuang 2L » Sun Feb 03, 2019 1:30 pm

Bond enthalpy is the least accurate because it represents the average of a series of different bonds from different molecules, so it represents an approximation of a bond rather than a more precise measurement like formation.

Hope that helps!
Last edited by Xuan Kuang 2L on Sun Feb 03, 2019 1:31 pm, edited 1 time in total.

Rimsha Hussaini 1A
Posts: 31
Joined: Fri Sep 28, 2018 12:20 am

Re: Why Bond Enthalpies are the least accurate

Postby Rimsha Hussaini 1A » Sun Feb 03, 2019 1:31 pm

A bond enthalpy is considered an estimate of the energy needed to break the average bond. Bonds can be either weakened or strengthened depending on the other atoms in the molecule associated with the bond and would need either less or more energy to break. Therefore, the bond enthalpy can be slightly different among different molecules.

Irene Zhou 1E
Posts: 73
Joined: Fri Sep 28, 2018 12:18 am

Re: Why Bond Enthalpies are the least accurate

Postby Irene Zhou 1E » Sun Feb 03, 2019 2:16 pm

Bond enthalpies are the averages of many bonds and are calculated under standard conditions. Thus, it can be slightly less accurate than the other methods.


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