Question:
Why is the reactivity of all the three classes of alcohols with conc? HCl and ZnCl2 (Lucas reagent) different?
Solution:
This is because of the steric hindrance of the alkyl group and the stability of carbocation.
Primary alcohol does not show any reaction at room temperature because the 1° carbocation is least stable.
Secondary alcohol does not show any turbidly at room temperature but on heating, turbidity appears.
Tertiary alcohol immediately shows turbidity after addition of Lucas reagent as they can form halides easily due to the higher stability of the carbocation.