Lucas test (ZnCl₂/HCl) for alcohol classification (Acid-catalyzed substitution to alkyl chloride; turbidity timing distinguishes alcohol)

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Acid-catalyzed substitution to alkyl chloride; turbidity timing distinguishes alcohol classes

What each symbol means

SymbolWhat it stands for
ROHAlcohol
ZnCl₂Lewis acid catalyst (Lucas reagent component)

When to use this

Anhydrous ZnCl₂ with conc. HCl; immediate turbidity 3°, delayed 1°; works best for ≤ six carbons in teaching examples.