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    That question about the difference in reactivity with bromine between Phenol, Bromine and Cyclohexene...

    Only worth 5 marks? I took up the whole page answering that question
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    (Original post by vazverma9)
    Siriously the peaks were small and its not just me alot of other people also counted 5, i dont understand the point of making them small.

    I guess its kind of my fault for not looking hard enough then again i was rushed for time and soo was most others
    dont worry i can definitely see how the mistake can be made :/
    i mustv done it millions of times before when practising so i always watch out for those tiny bumps (not even peaks lol) on the outside
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    (Original post by JoeHogan)
    That question about the difference in reactivity with bromine between Phenol, Bromine and Cyclohexene...

    Only worth 5 marks? I took up the whole page answering that question
    well you can be confident that you got 5 marks
    i actually didnt fill up the box, but should have put all the relevant info
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    Guys, not sure wether this has been mentioned already or not but for the TLC ( Thin layer chromatography ) - the process is not adsorption because the stationary phase is a solid and the mobile phase is a liquid in TLC, hence the process is seperation by relative solubility. In GC, the stationary phase is either a liquid or solid on a solid support with a mobile phase being a gas and therefore the process in GC for seperation is adsorption.
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    (Original post by MHorman)
    Valine on it's own isn't right.

    It's Valine, gylcine and leucine.
    I'm 100% on that one.
    Yeh I agree!
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    (Original post by win2kpro)
    Guys, not sure wether this has been mentioned already or not but for the TLC ( Thin layer chromatography ) - the process is not adsorption because the stationary phase is a solid and the mobile phase is a liquid in TLC, hence the process is seperation by relative solubility. In GC, the stationary phase is either a liquid or solid on a solid support with a mobile phase being a gas and therefore the process in GC for seperation is adsorption.
    TLC is always adsorption, the Silica gel (or Aluminium oxide) is polar.
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    (Original post by andy892)
    In paracetamol (I've now worked this out), there is a peptide bond.
    Is it possible that this could react with a halogenoalkane because the lone pair on the nitrogen atom would attack the electron defficient carbon in the C-X bond?
    Therefore, this would be a reagent used that would only react with paracetamol, as the same cannot be said for aspirin..
    Can a peptide bond also be called an amide bond?
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    (Original post by sa121)
    Can a peptide bond also be called an amide bond?
    isn't it just easier to call it a peptide bond?
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    (Original post by sa121)
    Can a peptide bond also be called an amide bond?
    think so yeah
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    Which ester are people thinking? (CH3)2CHCOOCH3 or CH3COOCH(CH3)2?
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    (Original post by Mr van der WAALs)
    For the last question I put:
    Reagent A: NaOH produce salt of carboxylate and phenolic salt
    Reagent B: KOH - reactive metal reacts with COOH functional group in asprin
    Reagent C: Br2 again - only reaction i could think of with phenol at the time :|
    I put all them 3 too right or wrong?
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    (Original post by Noble.)
    TLC is always adsorption, the Silica gel (or Aluminium oxide) is polar.
    True :o: I mixed the 2 up, sorry
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    (Original post by Woody.)
    Which ester are people thinking? (CH3)2CHCOOCH3 or CH3COOCH(CH3)2?
    without a shadow of a doubt
    (CH3)2CHCOOCH3
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    The question about the isoelectric points, what did everyone get? we didnt have to draw the whole amino acid did we?
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    guys i cant remeber exactly but i think it was the second question, where you they asked u to write the formula for the oxidation of an aldeyhde, i noticed also so that there was an -OH group. so i wrote that the product was a -COOH group on both ends.

    is that right??
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    In the oxidation question with potassium dichromate i didn't realise that the aldehyde AND the alcohol would be oxidised to a carboxylic acid!
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    (Original post by JordanCarroll)
    without a shadow of a doubt
    (CH3)2CHCOOCH3
    Was this the one NOT at the top right but below it? :confused:
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    (Original post by JordanCarroll)
    without a shadow of a doubt
    (CH3)2CHCOOCH3
    Balls. Why couldn't it have been the other?
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    (Original post by The_wise)
    guys i cant remeber exactly but i think it was the second question, where you they asked u to write the formula for the oxidation of an aldeyhde, i noticed also so that there was an -OH group. so i wrote that the product was a -COOH group on both ends.

    is that right??
    Yeah, I put that as well...is this the one where you get a dicarboxylic acid, and then you draw the mechanism? The mechanism was really hard to do for both sides...I don't know if I did it right, it seemed like an odd question :confused:
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    (Original post by Woody.)
    Balls. Why couldn't it have been the other?
    Because the shift values would've been completely different.
 
 
 
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