Concept:The Lucas test utilizes a specific mixture to differentiate primary, secondary, and tertiary alcohols based on the rate of alkyl chloride formation.
Formula:$$ \text{Lucas Reagent} = \text{Conc. HCl} + \text{Anhydrous ZnCl}_2 $$
Solution:- The reagent requires concentrated hydrochloric acid (HCl) as the halogen source and proton donor.
- It requires anhydrous zinc chloride (\(\text{ZnCl}_2\)) as a Lewis acid catalyst to coordinate with the oxygen atom, weakening the C-O bond.
- Therefore, Both B and C are required components of the Lucas reagent.
Why other options are incorrect:HCl or \(\text{ZnCl}_2\) alone is insufficient to constitute the active diagnostic reagent. \(\text{AlCl}_3\) is used in Friedel-Crafts reactions, not the Lucas test.
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