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    (Original post by Pedus)
    Would you get away with saying a gas is given off?
    No idea, sorry. I didn't know there was a gas lmao
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    (Original post by TwilightKnight)
    A + C should be ok, but NaBH4 still can't reduce a -COOH group by itself. Like I said before, they might ALLOW it due to confusing it with LiAlH4, but it's still not technically true.
    I didn't right NaBH4 for B i wrot KOH
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    (Original post by TwilightKnight)
    A + C should be ok, but NaBH4 still can't reduce a -COOH group by itself. Like I said before, they might ALLOW it due to confusing it with LiAlH4, but it's still not technically true.
    It's been said quite a few times. Two of the books for the course, including the one written by the Chief Examiner, allows the reduction of a carboxylic acid with NaBH4.
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    (Original post by Noble.)
    It's been said quite a few times. Two of the books for the course, including the one written by the Chief Examiner, allows the reduction of a carboxylic acid with NaBH4.
    I once saw on a Math paper that two completely irrelevant answers were given full method marks.

    It doesn't make them RIGHT, it just means that they've understood it would either be a common mistake or a common mixup with another compound. That's where we seem to have a difference of opinion.
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    (Original post by Noble.)
    It's been said quite a few times. Two of the books for the course, including the one written by the Chief Examiner, allows the reduction of a carboxylic acid with NaBH4.
    ****.

    I wrote NaBH4, but changed it to LiBH4 :facepalm: :facepalm:
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    (Original post by Noble.)
    It's been said quite a few times. Two of the books for the course, including the one written by the Chief Examiner, allows the reduction of a carboxylic acid with NaBH4.
    basically, dont mess with the colonel!
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    (Original post by BHAM!)
    I didn't right NaBH4 for B i wrot KOH
    I know, but you said you wanted at least 2 marks. KOH reacts with both. Bromine is iffy because Bromination generally doesn't take place in anything but primary Phenols. Not easilly at least... at least I think it doesn't.
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    I don't know why I read these threads, it just depresses me when I realise all the stupid mistakes I made. I NEED an A in chem D;
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    (Original post by The_wise)
    the mechanism was nucleophillic addition surely, it was for the reduction of the aldehyde to alcohol?

    am i right guys? x
    oh yeah, i got a dicarboxylic acid that is reduced though...
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    (Original post by TwilightKnight)
    I once saw on a Math paper that two completely irrelevant answers were given full method marks.

    It doesn't make them RIGHT, it just means that they've understood it would either be a common mistake or a common mixup with another compound. That's where we seem to have a difference of opinion.
    For the purpose of our course, they allow the reduction of a Carboxylic acid with NaBH4. I doubt two different books have made the same mistake multiple times throughout.
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    (Original post by TwilightKnight)
    I know, but you said you wanted at least 2 marks. KOH reacts with both. Bromine is iffy because Bromination generally doesn't take place in anything but primary Phenols. Not easilly at least... at least I think it doesn't.
    right so bromine for part C would be wrong? and KOH for B would be wrong? :sigh:
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    I thought it was a pretty good paper, finished with 10 minutes to go despite only reading the textbook this morning. Everyone else found it tricky :s:
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    (Original post by Noble.)
    For the purpose of our course, they allow the reduction of a Carboxylic acid with NaBH4. I doubt two different books have made the same mistake multiple times throughout.
    Aaaaaaaaaaahhhh.

    I KNOW they do. What im saying is that it isn't scientifically correct, and sometimes they overlook stuff like that.
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    (Original post by BHAM!)
    right so bromine for part C would be wrong? and KOH for B would be wrong? :sigh:
    Potassium hydroxide is definitely wrong since COO-K+ would be generated in Aspirin and O-K+ would be generated in Paracetamol.

    Im not sure about the Bromine. I remember reading that anything other than Phenol resists Bromination like that due to the Pi-bond delocalisation. Don't quote me on it.
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    (Original post by steph_v)
    I don't know why I read these threads, it just depresses me when I realise all the stupid mistakes I made. I NEED an A in chem D;
    totally know how you feel there!
    thought i'd done pretty good in this exam till I read this thread realised all the stupid mistakes
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    Guyss i couldnt get my head aorund the sterio isomerism drawingss????!!!!!!! wat was that abouttt? :\
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    (Original post by BeeJay)
    Guyss i couldnt get my head aorund the sterio isomerism drawingss????!!!!!!! wat was that abouttt? :\
    2 pairs of optical isomers
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    (Original post by M_J)
    totally know how you feel there!
    thought i'd done pretty good in this exam till I read this thread realised all the stupid mistakes
    samee!! its so depressingg, i was aiminggg for such a high A butt nowww it sucks
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    (Original post by Pedus)
    basically, dont mess with the colonel!
    do you go to havant college too?
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    (Original post by desertwarrior)
    2 pairs of optical isomers
    i knew there was 2 chiral centres, each with 2 isomers hence 4, but how would yu draw then?? it was the way it was drwan that really put me off!
 
 
 
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