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    Hey does anyone know the test for an alcohol?
    Is it potassium Dichromate?
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    (Original post by sophieo128)
    Hey does anyone know the test for an alcohol?
    Is it potassium Dichromate?
    There are many tests for alcohols.
    - Add sodium = white precipitate and effervescence
    - Acidified sodium/potassium dichromate = turns orange to green with primary and secondary alcohols, remains orange with tertiary.
    - PCl5 - misty white fumes of HCl
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    (Original post by Peppercrunch)
    There are many tests for alcohols.
    - Add sodium = white precipitate and effervescence
    - Acidified sodium/potassium dichromate = turns orange to green with primary and secondary alcohols, remains orange with tertiary.
    - PCl5 - misty white fumes of HCl
    Thank You so much!
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    You add acidified potassium dichromate (K2Cr2O7)
    This is causes the alcohol to undergo an oxidation reaction.
    If it is alcohol, the sample will turn green from orange.
    Mind you, this only turns colour with primary and secondary alcohols since tertiary alcohols can't undergo oxidation.
    Aldehydes will also turn green from orange (since they can oxidise further to a carboxylic acid)
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    There's also an additional test. Add it to a carboxyllic acid along with concentrated sulfuric acid and distil. If there is a fruity smelling odor then an alcohol is present, since an ester is formed.
 
 
 
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