Question

An unknown alcohol is treated with "Lucas reagent" to determine whether the alcohol is primary, secondary, or tertiary. Which alcohol reacts fastest and by what mechanism?

• A. Secondary alcohol by SN₁
• B. Tertiary alcohol by SN₁
• C. Secondary alcohol by SN₂
• D. Tertiary alcohol by SN₂

Hint:

Lucas reagent test works on carbocation stability, making tertiary alcohols the fastest-reacting.

Answer 1

The Correct Option is B

Step 1: Lucas Test Principle
- The Lucas test distinguishes alcohols by their reaction with ZnCl₂/HCl.
Step 2: Reactivity Sequence
- Tertiary alcohols exhibit the highest reactivity, proceeding through the S_N1 mechanism.
Conclusion: Tertiary alcohol via S_N1.