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    (Original post by zirak46)
    Pastpapers.org or something like that.

    Ive been going through them and tbh theyre not THAT great help. Only gone through first 4 exams though but they dont seem as helpful for f325

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    Oh that's a shame. But thank you

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    (Original post by ImNervous)
    Oh that's a shame. But thank you

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    Thats just me though.

    They were super useful for f321 but I dont know why Im not gettig any extra from these ones.

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    (Original post by zirak46)
    Thats just me though.

    They were super useful for f321 but I dont know why Im not gettig any extra from these ones.

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    What about for f324

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    (Original post by ImNervous)
    What about for f324

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    Im not doing f324 so I wouldnt know. But i have seen plenty for it. If i was doing it, i would definately go through them. Its what im doing for f325, just havent found it as helpful as f321 legacy papers for me. Hopefully its only cause ive done 4 out of 9 I think.

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    For F324 I've come across loads of questions where phenylamines are reacted with HNO2 and HCl, so you would form a diazonium ion, but how do I know whether to put just the ion or to display the Cl- as well (diazonium salt?) any help would be appreciated.
    Secondly, the question i've attached - I understand the product structures, but on the mark scheme the NH becomes NH3+ and the N becomes NH2+. Is this always the case with acid hydrolysis? I thought the NH would become NH2 not NH3+, and the N would become NH not NH2+. It doesn't mention excess acid. Maybe I need to take a break as I'm confusing myself - hope this makes some sense.
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    (Original post by Heisenberg___)
    Came across this fantastic link for old chemistry past papers. The person who made this has also kindly highlighted questions that we can skip (as they aren't relevant to our spec). Enjoy!

    http://www.chemhume.co.uk/A2CHEM/Exa...additional.htm
    Thanks, why don't the unit five papers have any questions in red? Is the spec still the same for unit five?

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    (Original post by mechanism)
    For F324 I've come across loads of questions where phenylamines are reacted with HNO2 and HCl, so you would form a diazonium ion, but how do I know whether to put just the ion or to display the Cl- as well (diazonium salt?) any help would be appreciated.
    Secondly, the question i've attached - I understand the product structures, but on the mark scheme the NH becomes NH3+ and the N becomes NH2+. Is this always the case with acid hydrolysis? I thought the NH would become NH2 not NH3+, and the N would become NH not NH2+. It doesn't mention excess acid. Maybe I need to take a break as I'm confusing myself - hope this makes some sense.
    Usually the Cl- is ignored in the Markscheme - you can put it down but you won't lose or gain any marks.

    With your second question, acid hydrolysis will ALWAYS form NH3 because of the lone pair of electrons on the nitrogen atom. They're hungry for a proton, so will grab it whenever they have a chance to.
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    (Original post by RayMasterio)
    Usually the Cl- is ignored in the Markscheme - you can put it down but you won't lose or gain any marks.

    With your second question, acid hydrolysis will ALWAYS form NH3 because of the lone pair of electrons on the nitrogen atom. They're hungry for a proton, so will grab it whenever they have a chance to.
    Thanks so much for the clarification. In the book, hydrolysis of an amide link just shows formation of -NH2 and -COOH, but I get it now!
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    (Original post by pineneedles)
    Thanks, why don't the unit five papers have any questions in red? Is the spec still the same for unit five?

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    I think the unit 5 papers on that site have already been edited to take out questions which are no longer on the specification.
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    (Original post by marioman)
    I think the unit 5 papers on that site have already been edited to take out questions which are no longer on the specification.
    Oh right, I see. Thanks

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    <a href="http://tinypic.com?ref=mcbrtj" target="_blank"><img src="http://i65.tinypic.com/mcbrtj.png" border="0" alt="Image and video hosting by TinyPic"></a>

    can someone please tell me why the reduction process is wrong? Is a reduction of a COOH always OH? Or is it because we are polymerising so it must be COOH + OH to form the peptide link?
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    To be honest I don't find the legacy papers that much of a help. Not in pushing the difficulty anyway.

    Although they're good for repetition.


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    Does anyone have the mark scheme for the 2015 F324 paper? I've done the paper and want to get it marked.
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    (Original post by thad33)
    To be honest I don't find the legacy papers that much of a help. Not in pushing the difficulty anyway.

    Although they're good for repetition.


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    Do harder questions then.
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    (Original post by alow)
    Do harder questions then.
    I was openly replying to whoever was asking about the legacy papers.

    Thank you very much for the advice though, it was invaluable.
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    (Original post by alow)
    Do harder questions then.
    Woah that aggression.
    Which questions do you suggest? From past papers? Theres only 8 and I dont want to use all of them up so soon. I need some for the days before the exam

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    (Original post by thad33)
    To be honest I don't find the legacy papers that much of a help. Not in pushing the difficulty anyway.

    Although they're good for repetition.


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    Totally agree
    Ive done the first four past papers of f325 and first 3 papers of unifying concepts and trends&patterns each.

    The actual f325 ones obviously helped massively but the legacy ones arent that helpful. How many of you done of f325 and legacy? And what are you doing now?
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    (Original post by zirak46)
    Woah that aggression.
    Which questions do you suggest? From past papers? Theres only 8 and I dont want to use all of them up so soon. I need some for the days before the exam

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    How exactly was that aggressive? Calm down dear.

    There are more resources than just past papers.
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    (Original post by alow)
    How exactly was that aggressive? Calm down dear.

    There are more resources than just past papers.
    please link sir
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    Is this off-topic?

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