The reaction of tert-butyl alcohol t-BuOH with hydrochloric acid HCl to produce tert-butyl chloride t-BuCl is an example of an acid-catalyzed substitution reaction, specifically a nucleophilic substitution at a tertiary carbon SN1 mechanism .Here is the step-by-step mechanism and intermediates involved in this reaction:1. Protonation of tert-butyl alcohol: The oxygen atom of the tert-butyl alcohol molecule acts as a nucleophile and attacks the hydrogen atom of the hydrochloric acid molecule. This results in the formation of a protonated tert-butyl alcohol t-BuOH2+ and a chloride ion Cl- .Intermediate: Protonated tert-butyl alcohol t-BuOH2+ 2. Formation of carbocation: The protonated tert-butyl alcohol molecule undergoes heterolysis, where the bond between the oxygen and the tertiary carbon breaks. The oxygen atom takes both electrons from the bond, leaving a positively charged tert-butyl carbocation t-Bu+ and a water molecule H2O .Intermediate: Tert-butyl carbocation t-Bu+ 3. Nucleophilic attack: The chloride ion Cl- acts as a nucleophile and attacks the positively charged tert-butyl carbocation t-Bu+ , forming a new bond between the chloride ion and the tertiary carbon. This results in the formation of the tert-butyl chloride t-BuCl product.Product: Tert-butyl chloride t-BuCl Overall, the reaction proceeds through two intermediates: protonated tert-butyl alcohol t-BuOH2+ and tert-butyl carbocation t-Bu+ . The mechanism involves an acid-catalyzed nucleophilic substitution at a tertiary carbon SN1 mechanism .