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Phenol and alcohol question Watch

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Size:  354.6 KB The question asks to identify A, B and C. When testing for C, I was thinking about using acidified potassium dichromate as C contains an alcohol; the predition is the colour will change from orange to green. I am not sure whether A will interfere with this test. Does phenol also behave as an alcohol as does it only behave as an acid?

    Thanks!
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    C is an alcohol, so can be oxidised.
    A can't - you'd have to disrupt the delocalised ring to turn it into a ketone.
    B is an ether, so doesn't have a carbonyl group to react with 2,4-DNP.
    Don't both A and B have an O (with a lone pair) attached to the ring, so wouldn't both decolourise Br2(aq)?
    Better to use the weak acid properties of phenols (A) and react with Na (-> H2) or with neutral iron(III) chloride.
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    (Original post by Pigster)
    C is an alcohol, so can be oxidised.
    A can't - you'd have to disrupt the delocalised ring to turn it into a ketone.
    B is an ether, so doesn't have a carbonyl group to react with 2,4-DNP.
    Don't both A and B have an O (with a lone pair) attached to the ring, so wouldn't both decolourise Br2(aq)?
    Better to use the weak acid properties of phenols (A) and react with Na (-> H2) or with neutral iron(III) chloride.
    How do you test for B then? Thanks
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    Hi!

    You can test for A using aqueous bromine as it will give a white precipitate (and probably an antiseptic smell); only A reacts with Br(aq) in this case.

    As you've guessed, acidified potassium dichromate can be used to identify C, solution changes from orange to green.

    You can then separate compound B.

    Hope it helped!
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    (Original post by bleak_rage)
    ...only A reacts with Br(aq) in this case.
    Anisole will also react with Br2 (like I suggested before).

    I don't know of a test for ethers, you'll have to make do with no result as your positive. Sort of.
 
 
 
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