I understand that the heat of combustion per carbon is a way of determining whether one compound is more stable than another. Would you expect the heat of combustion per carbon for an alkene to be higher or lower than an alkane?
Heat of Combustion Question
- Thread starter kfcman289
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Comparing Ethane to Ethene (wiki it) you see Ethane has a larger heat of combustion.
Benzene is a common example because it is more stable than cyclohexane, it has a lower heat of combustion per carbon from the partial double bond character and stability.
If you compare cycloprop-ane to cycloprop-ene the alkene form is much less stable due to larger ring strain from the double bond, so the heat of combustion for the alkene here is much higher.
It really boils down to stability and where the double bond is located, but usually double bonds stabilize molecules.
Benzene is a common example because it is more stable than cyclohexane, it has a lower heat of combustion per carbon from the partial double bond character and stability.
If you compare cycloprop-ane to cycloprop-ene the alkene form is much less stable due to larger ring strain from the double bond, so the heat of combustion for the alkene here is much higher.
It really boils down to stability and where the double bond is located, but usually double bonds stabilize molecules.
