Primary, secondary and tertiary alcohols can be distinguished by:
Show Hint
- Lucas test
- Fehling's test
- Tollens' test
- Hinsberg's test
The Correct Option is A
Solution and Explanation
Lucas test is used to distinguish between primary, secondary, and tertiary alcohols based on their reactivity with Lucas reagent (conc. HCl + anhydrous ZnCl\(_2\)). Reaction: Alcohol \( \rightarrow \) Alkyl chloride (insoluble, turbidity appears)
Step 1: Basis of differentiation. The rate of formation of turbidity differs:
- Tertiary alcohol → Immediate turbidity
- Secondary alcohol → Turbidity in few minutes
- Primary alcohol → No turbidity at room temperature
Step 2: Eliminate incorrect options.
- Fehling's test → For aldehydes
- Tollens' test → For aldehydes
- Hinsberg's test → For amines
Step 3: Final answer. \[ \therefore \text{Correct answer = Lucas test} \]
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