SN1 reaction undergoes through a carbocation intermediate as follows:

[R = t-Bu, iso-Pr, Et, Me] $(X = C l, B r, I)$
The correct statements are:
I. The decreasing order of rate of SN1reaction is $t - B u X > i s o - P r X > E t X > M e X$
II. The decreasing order of ionization energy is $M e X > E t X > i s o - P r X > t - B u X$
III. The decreasing order of energy of activation is $t - B u X > i s o - P r X > E t X > M e X$

Question

SN1 reaction undergoes through a carbocation intermediate as follows:

[R = t-Bu, iso-Pr, Et, Me] $(X = C l, B r, I)$
The correct statements are:
I. The decreasing order of rate of SN1reaction is $t - B u X > i s o - P r X > E t X > M e X$
II. The decreasing order of ionization energy is $M e X > E t X > i s o - P r X > t - B u X$
III. The decreasing order of energy of activation is $t - B u X > i s o - P r X > E t X > M e X$

Toppr Admin · Accepted Answer

I and II are correct-Explanation-1- Formation of the carbocation is Rate determining step- more stable the cation more easily it will form- Hence rate order is t-x2212-BuX-gt-iso-x2212-PrX-gt-EtX-gt-MeX-2- Formation of carbocation CH3 is most difficult hence ionization energy is highest- Similarly- EtX has lesser ionization energy than MeX and so on-3- Order of energy of activation is MeX-gt-EtX-gt-iso-x2212-PrX-gt-t-x2212-BuX