Question

How many Statements are correct below?
A. Groups showing $+I$ effect stabilize electron deficient species and destabilize electron rich species.
B. Groups showing $+I$ effect destabilize electron deficient and electron rich species.
C. Groups showing $-I$ effect stabilize electron rich species and destabilize electron deficient species.
D. Groups showing $-I$ effect stabilize electron deficient species and stabilize electron rich species.

Answer 1

Groups showing $+I$ effect:
They are electron donating groups. So, when these groups are attached to an electron deficient species, they will neutralize their positive charge and make them stable. On the other hand when a group showing $+I$ effect is attached to an electron rich species. It will make the electron rich species even more negatively charged by donating electrons, hence making then unstable.

Groups showing $-I$ effect:
They are electron withdrawing groups. So, when these groups are attached to an electron rich species, they will neutralize their negative charge by withdrawing electrons and make them stable. On the other hand, when a group showing $-I$ effect is attached to an electron deficient species, it will make the electron deficient species even more positively charged by withdrawing electrons, hence making them unstable.

Option A and C are correct.