Answer: it is an SN1 mechanism.
Step-by-step explanation:
The reaction between 2-methyl-2-pentanol and HBr to yield 2-methyl-2-pentene is an SN1 mechanism.
WHAT IS AN SN1 REACTION: SN1 is a substitution reaction in which the reaction centre gives racemization of stereochemistry. Also, SN1 reaction are unimolecular.
In SN1, the rate determining step depends on the decomposition of a single molecular species. At the intermediate, there is carbocation in this reaction.
SN1 REACTION MECHANISM: The following are the steps involving the mechanism for SN1 reaction of 2-methyl-2-pentanol with HBr.
Step 1:
ACID-BASE REACTION: here, we have the protonation of the oxygen in the alcohol. The protonation makes it a good leaving group.
Step 2:
C-O CLEAVAGE: the C-O bond breaks. This bond breaking is endothermic and this step is the rate determining step.
Step 3:
ATTACK ON THE BROMIDE ION.
The equation of reaction is given below:
C6H15O + HBr ------------> [intermediate] --------------> C6H12 (2-methyl-2-pentene).