Jshek
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So cyclohexatriene is -360 and benzene is -208kjmol^-1

I don't get why it is harder to break the bond in benzene which will make it more stable.
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jm4761
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The numbers you've given aren't bond enthalpies, they're actually hydrogenation enthalpies.

Essentially, the numbers represent how much energy is released when you react the structure with H2 to turn it into cyclohexane.

It turns out that for every double bond you hydrogenate into a single bond, it releases about 120 kJ/mol of energy. If benzene wasn't special, and was simply cyclohexatriene, we would expect complete hydrogenation to release 360 kJ/mol of energy, because there are 3 double bonds and 120*3=360.

However, we actually observe that hydrogenating benzene only releases 208 kJ/mol of energy. This basically means that benzene is about 150 kJ/mol more stable than we would expect if it didn't have any special properties, which is in line with what we know about the effects of aromaticity.

Does that make sense?
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