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    Okay, my two textbooks say the exact opposite. One says that to oxidise a benzene side chain to -COOH you use hot alkaline KMnO4. The other book says you use aqueous acidified KMnO4. Which one is it?!
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    This is edexcel btw
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    aromatic compounds with carbon-containing side chains with alkaline potassium
    manganate(VII) solution, resulting in the oxidation of the side-chains

    this is from the specification, so i guess it is alkaline.
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    alkaline
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    you cant use acidic.
    it is alkaline
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    Okay, one more question - how do u make nitrous acid?
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    (Original post by KP Nuts)
    Okay, one more question - how do u make nitrous acid?
    i think there are a few ways, but for diazonium ions i know you need to make it in situ using Sodium nitrite and hydrochloric acid, so you can then react it with phenylamine...

    NaNO2 + HCl --> HONO + NaCl
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    this unit 5 is gonna be tough.. i wish i learnt it earlier argh
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    i only started my revision yesterday nite :eek: its a gd thing chemistry isnt part of my offer :rolleyes: anyways gd luck
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    (Original post by riks2004)
    i only started my revision yesterday nite :eek: its a gd thing chemistry isnt part of my offer :rolleyes: anyways gd luck
    i started this morning!!!!!! i need at least a B
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    (Original post by cjoc28)
    i started this morning!!!!!! i need at least a B

    :eek: wat u get at a/s?
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    (Original post by riks2004)
    :eek: wat u get at a/s?
    B i didnt do any revision last year either

    this is gonna be hard tho
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    i revised really hard last year for chemistry n only ended up with a C, ent dun no revision this year so wont be hard to predict wat ill get lol
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    u used hot alkaline but then u have to ACIDIFY it...thats probably what the book meant...
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    I hope you put alkaline today!
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    Yup, did u put 'in NaOH' to give the -COONa?
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    I just put KMnO4 in alkaline solution, hopefully thats enough to get the mark but thinking about it, I'm not sure it will be. Argh, think I've lost a few marks on general sloppyness
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    humm - but don't you use ACIDIFIED KMnO4 to oxidise alcohols - maybe the two books are talking about the two different cases
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    (Original post by danguetta)
    humm - but don't you use ACIDIFIED KMnO4 to oxidise alcohols - maybe the two books are talking about the two different cases
    It's acidified potassium dichromate (VI) to oxidise alcohols

    Potassium Manganate (VII) in NaOH does 2 things - will oxidise any side chains of a benzene ring to the sodium salt which is then acidified to COOH using a dilute acid. Also forms a diol when reacted with alkene
 
 
 
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