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
Step 1: Understanding the Lucas test. Lucas reagent consists of \[ ZnCl_2 + HCl \] Alcohols react with this reagent to form alkyl chlorides. \[ ROH + HCl \rightarrow RCl + H_2O \] The alkyl chloride formed is insoluble and produces turbidity.
Step 2: Observing the behaviour of different alcohols. Tertiary alcohols react immediately and produce turbidity instantly. Secondary alcohols react more slowly and produce turbidity within a few minutes. Primary alcohols react very slowly and usually show no turbidity at room temperature. Therefore, alcohols can be distinguished based on the time taken to produce turbidity.
Step 3: Checking the remaining options. Fehling's test is used for aldehydes. Tollens' test is also used for aldehydes. Hinsberg's test is used for distinguishing amines. Thus none of these tests can distinguish alcohols. Therefore, the correct answer is Lucas test. \[ \boxed{\text{Option (A)}} \]
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