Applications of hyperconjugation

(A) Carbon-carbon double bond size in alkenes: As we know previously that the more is the number of resonating structures, the very much will be single bond character in carbon-carbon double bond.

(B) Durability of alkyl carbocations : Stability of alkyl carbocations µ number of resonating structures µ number of alpha hydrogens.

(C) Stability of alkyl free radicals : Stability of alkyl free radicals can be described through hyperconjugation. Stability relays upon the some number of resonating structures.

(D) Electron releasing (or donating) power of R in alkyl benzene : CH^3- (or alkyl group) is +R group, ortho-para directing set and activating set for electrophilic aromatic substitution reaction due to the hyperconjugation.

The electron donating power of alkyl group will relies on the number of resonating structures, this relays on the number of hydrogens available on a-carbon. The electron releasing power of some groups are like this,