In hood: Add 4 or 5 drops or 30 - 50 mg of unknown to 2 mL of pure chloroform in a clean, dry test tube. Stir the solution. If the unknown does not dissolve, even partially, add 2 - 3 mL more chloroform and warm gently. Cool to 25oC and add 2 drops of 1% solution of anhydrous ferric chloride in chlorofrom followed by 3 drops of pyridine. Shake the test tube and note the color produced immediately.
The appearance of blue, violet, purple, green, or red-brown color is a positive test.
Not all phenols or enols give positive results.
Most oximes, hydroxamic acids, and sulfinic acids give a positive test.
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