For the E1 dehydrohalogenation of 2-chloro-2-methylpropane in ethanol (no added strong base), the rate law is

A $rate = k [C X_{2} H X_{5} O X^{-}]$
B $rate = k [RCl]^{2}$
C $rate = k [RCl] [C X_{2} H X_{5} O X^{-}]$
D $rate = k [RCl]$

Answer: D

E1 is a two-step process whose slow step is ionisation of the C-Cl bond to the carbocation. The base (solvent) acts only after the slow step, so it does not appear in the rate law. Hence rate =

k [RCl]

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For the E1 dehydrohalogenation of 2-chloro-2-methylpropane in ethanol (no added strong base), the rate law is

Answer: D

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