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Which of the following exhibits both inductive effect and hyperconjugation?
A) $ C{H_3} - C{H_3} $
B) $ C{H_3} - C{H_2} - Cl $
C) $ C{H_3} - OH $
D) $ C{H_3} - (CH)_2^ + $

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Last updated date: 23rd Jul 2024
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Answer
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Hint :Sigma bonds are polarised by the inductive effect. The interaction between sigma bonds and p orbitals or pi bonds is known as hyperconjugation, which is close to "resonance."

Complete Step By Step Answer:
Inductive Effect
The inductive effect is a chemistry term for the transfer of unequal bonding electron sharing across a chain of atoms in a molecule, resulting in a permanent dipole in a bond. In contrast to the electromeric effect seen in a pi bond, it is present in a sigma bond.
Alkyl halide has electron withdrawing halogen atoms, while the alkyl groups have electron donating tendencies. The positive charge is relayed to the other atoms in the chain if the electronegative atom (missing an electron, hence possessing a positive charge) is joined to a chain of atoms, normally carbon. This is the -I effect, or the electron-withdrawing inductive effect. In a nutshell, alkyl groups donate electrons, resulting in the +I effect. The ionisation constant serves as its experimental foundation. It differs from, and often opposes, the mesomeric effect.
Hyperconjugation
Hyperconjugation (or $ \sigma $ -conjugation) is a term used in organic chemistry to describe the delocalization of electrons when mainly -character bonds are involved. The electrons in a sigma ( $ \sigma $ ) orbital (e.g. $ C - H $ or $ C - C $ ) interact with an adjacent unpopulated non-bonding p or antibonding $ {\sigma^*} $ or $ {\pi^*} $ orbital to form a pair of extended molecular orbitals.
Low-lying antibonding $ {\sigma^*} $ orbitals, on the other hand, can interact with filled orbitals of lone pair character (n) in a process known as 'negative hyperconjugation. The system's stability is improved by increased electron delocalization associated with hyperconjugation.
Due to the presence of H-atoms in the $ C{H_3} $ group, $ C{H_3} - (CH)_2^ + $ will display hyperconjugation, as well as an inductive effect due to the lack of symmetry.
The correct option is D.

Note :
Hyperconjugation has been proposed as a key factor in sigma bond shortening. The heats of hydrogenation per double bond are less than the heats of hydrogenation of ethylene, and the heats of formation of molecules with hyperconjugation are greater than the number of their bond energies.