Bond Enthalpies

[Tiffany Cao 1D]

Why is using bond enthalpies the most unreliable form of calculating reaction enthalpy?

[Ryan Sydney Beyer 2B]

I believe that bond enthalpies are the most unreliable method for calculating reaction enthalpies because the bond enthalpies are not specific to the specific molecules in the reaction. Instead, the bond enthalpies are averaged over many different molecules. For example, a C-H bond in one molecule might be different from another molecules based on what else is in the molecule, so the average might be somewhere in the middle.

[Ammarah 2H]

Are the bond enthalpies for the diatomic molecules accurate or are they also averages?

[Melodie Oh 2A]

This is because bond enthalpies uses the average bond, and doesn't take the intermolecular forces into account.

[CalebBurns3L]

Bond enthalpies represent averages, and do not accurately represent the enthalpies specific to a certain molecule.

[204932558]

Bond enthalpy is an average value of the energies required to break/form a certain type of bond in MANY MOLECULES. Therefore each molecule's bond enthalpy differs.