Bond energy of a Pi bond and a sigma bond

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The discussion highlights a common misconception regarding the strength of sigma and pi bonds, noting that while sigma bonds are generally stronger, specific bond energy values can suggest otherwise. The bond energy table indicates that the C=O bond has an energy of 745 KJ, while the C-O bond is at 358 KJ, leading to the calculation that the pi bond energy is 387 KJ. This raises the question of how a pi bond could appear stronger than a sigma bond. It is clarified that the comparison involves different hybridizations, with the C-O bond being sp3 hybridized and the C=O bond being sp2 hybridized, making the comparison invalid. Understanding the hybridization context is crucial for accurate bond strength assessments.
r12214001
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bond energy
It is well known that sigma bond is stronger than Pi bond. However in bond energy table that C=O is 745 KJ and C-O is 358 KJ. we can calculate the Pi bond energy is 745-358=387! The Pi bond(387KJ) is stronger than sigma bond(358KJ) ? How could this happen?
 
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r12214001 said:
Summary: bond energy

It is well known that sigma bond is stronger than Pi bond. However in bond energy table that C=O is 745 KJ and C-O is 358 KJ. we can calculate the Pi bond energy is 745-358=387! The Pi bond(387KJ) is stronger than sigma bond(358KJ) ? How could this happen?
In this case, your table lists the sp3 hybridized sigma carbon-oxygen strength ( C-O) rather than the sp2 hybridized sigma carbon-oxygen strength (C=O). Comparing apples and oranges...
 
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... and the CO bond is shorter.
 
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