Chapter 5, Problem 5.27P

Interpretation Introduction

Interpretation:

From the given molecules, which one has the smaller heat of combustion is to be identified and the reason for it is to be explained.

Concept introduction:

If the two molecules are isomers of each other, they have precisely the same combustion products. As a result, any difference in the heat of combustion must be attributed to differences in stabilities of the alkenes. The most stable compound has smallest heat of combustion. Double bond stability increases as the amount of alkyl substitution increases due to hyperconjugation. The alkyl substitution is the number of alkyl groups bonded to the alkene carbon atoms.