What is a spot test for alcohol?

Is there a litmus test or some other test which can determine if alcohol is present in an unknown substance?
Mike Jeffery

The classic test for alcohols uses chromic anhydride (CrO3) in sulfuric acid solution. Within seconds after contacting a sample containing alcohol, the solution turns from clear orange to cloudy blue-green. Be careful- chromic anhydride in acid is extremely corrosive, poisonous, and carcinogenic.

You can detect grain, wood or rubbing alcohol with the "iodoform test". Treat the sample with iodine and sodium hydroxide; if these alcohols are present, you get a cloudy yellow precipitate (CHI3). The test can be fooled by some ketones (for example, nail polish remover will give a positive test because it contains acetone).

Author: Fred Senese senese@antoine.frostburg.edu



General Chemistry Online! What is a spot test for alcohol?

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