Regarding ${\mathrm{SN}}^1$ mech, correct statements are

A) Most reactive species leads to the formation of most stable corbocation

B) Carbocation intermediate is formed 

C) Taken place in polar protic solvents

D) Solvents are water, alcohols, acetic acid

E) unimolecular reaction 

F) non-concerted reaction 

G) Rate $\propto \left[RX\right]$

Energy required to break C - X bond is obtained through solvation. Polar protic solvents like $H_{2}O,C_2{H}_{5}OH,C{H}_{3}COOH$ can easily produce 

carbo cation.

Rate limiting step involves carbocation formation 

Rate of $S{N}^1\propto$stability of $\stackrel{+}{C}$ 

Slow step involves only R - X

unimolecular, Rate = K [RX]

it occurs in more than one step, non-concerted