Place 5 mL of 10% sodium hydroxide solution in a test tube, add 0.2-0.4 g of the compound, and shake the mixture vigorously. Note the odor of ammonia or the formation of an oily layer of the amine. Moistened pink litmus paper placed in the vapor above the solution will turn blue if ammonia or a volatile amine is present.
ammonium salts - ammonia smell is a positive test.
amine salts - separation of an oily layer of the amine is a positive test.
None.
To 5 mL of 20% sodium hydroxide solution add 2 mL of ethanol and a drop or a crystal of the unknown, and shake vigorously. Note the color of the solution.
mononitro compounds - light yellow color is a positive test.
dinitro compounds - bluish purple color is a positive test.
trinitro compounds - blood red color is a positive test.
The presence of amino or hydroxyl groups inhibits the formation of these colored solutions.
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