The test used to distinguish among primary, secondary and tertiary alcohols is:
Correct answer: C. Lucas test
- A. 2, 4 - DNPH test
- B. Tollen's test
- C. Lucas test
- D. Fehling's solution test
Explanation
The "Lucas test" uses Lucas Reagent, which is a solution of Anhydrous zinc in concentrated H2SO4. The test determines whether alcohol is primary, secondary, or tertiary based on how readily the alcohol gives hydroxyl ions to replace the chloride in zinc chloride. Primary alcohols show the least turbidity (haziness of the liquid's surface indicating that a reaction took place), meaning that it does not react quickly with Lucas Reagent at room temperature. Secondary alcohols show medium turbidity, while tertiary alcohols show the most, meaning that they react readily with Lucas Reagent.
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About Alcohols
Alcohols contain a hydroxyl group attached to a saturated carbon atom and are classified as primary, secondary or tertiary. Their nomenclature, hydrogen bonding, acidity, oxidation, dehydration, reaction with sodium and conversion to haloalkanes are covered, along with the distinction between alcohols and phenols, where the hydroxyl group is attached directly to an aromatic ring.
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