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Test 4: Lucas test A final test is the Lucas test. In this test, you will use zinc chloride to distinguish between primary, secondary and tertiary alcohols. This test is not redox and it will not identify phenol. A primary alcohol, when reacted with the hydrochloric acid and zinc chloride will not react. Secondary and tertiary alcohols will form an insoluble product upon heating. The secondary alcohol reacts much more slowly so you must observe not only IF a precipitate occurs but also HOW LONG it takes that insoluble substance to be produced. Primary alcohol + HCl + ZnCl2 → No reaction Secondary alcohol + HCl + ZnCl → Insoluble product (after 10 minutes in heat) Tertiary alcohol + HCI + ZnCl2 → Insoluble product (less than 5 minutes in heat) To perform the Lucas test, get 7 clean, dry test tubes. Into each place 5 drops of the alcohol. Add 1 mL of the Lucas reagent and mix thoroughly. Let the test tubes stand for 15 minutes and record your observations below. Remember, cloudiness indicates the formation of a precipitote. Place any tubes that remain clear into a 60°C water bath, noting the time required for any change. Alcohol Observations Is the reacting alcohol 1929, or 3? Ethanol 2-propanol 2-methyl-2-propanol Phenol Unknown alcohol A Unknown alcohol B Unknown alcohol What did you learn about the identity of the unknowns from this test? Explain. Post-lab: 1). Identify each unknown and explain how you came to your conclusion. The possible unknowns are listed in the second table on page 2 Unknown Letter A Unknown Letter B name of unknown name of unknown name of unknown Unknown Letter C Explanation: