Question

In which of the following species, correct direction of inductive effect is shown?
A)

B)

C)

D) None of the above.

Answer 1

Hint: We know Inductive effect means the polarization of the sigma bond due to electron attracting and electron releasing effect of an adjacent atom.
\[C{H_3}^{\delta + + } - C{H_2}^{\delta + } - C{l^{\delta - }}\]
We have two types of inductive effect namely positive inductive effect (+I) and negative inductive effect (-I).

Complete step by step answer:
We know that an inductive effect is usually due to an electronegativity difference between the atoms at both the end of the bond. The more electronegative atom attracts the electrons in the bond towards itself creating bond polarity.
In the option both oxygen and nitrogen are more electronegative than carbon. They should pull the electrons and the arrow must be pointed towards nitrogen. Thus, the direction of the arrow is wrong.
Therefore, the option A is wrong.
In options (B) and (C), both the carbons are attached to nitrogen and oxygen respectively which are more electronegative than carbon. The carbon bonded to the Oxygen and Nitrogen shall attain partial negative charge and pull the electrons toward it.

Therefore, the options (B) and (C) are correct.

Note:
Positive inductive effect:
An atom or a group which attracts electrons towards itself less than a hydrogen atom is known as an electron-donating group and they are said to have a positive inductive effect (+I). Some of the groups with +I effects are $ - C{H_3}$,$ - {C_2}{H_5}$,${\left( { - C{H_3}} \right)_3}$ etc…
Negative inductive effect:
An atom or a group which attracts electrons towards itself more strongly than a hydrogen atom is known as an electron attracting group and they are said to have a negative inductive effect (-I). Some of the groups with -I effects are $ - Cl$,$ - N{O_2}$,$ - Br$,$ - I$ etc…

We also remember that an inductive effect is different from the resonance effect in which the sigma electrons, pi electrons and inductive effect are involved.