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    (Original post by Conor 419)
    I'm good now with all of the Kw, Ka, Kg, Klol etc calculations. However I'm still struggling to get buffers. I understand that they maintain a constant pH with the addition of acid or Alkali, but I'm struggling to see how.

    Some reasons why I'm confused.

    |Does every buffer contain a Weak Acid/Conjugate Acid AND a Weak Base/Conjugate Base working together?
    They contain one of those sets.
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    What decides why I'd use one set over the other?
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    (Original post by Conor 419)
    I'm good now with all of the Kw, Ka, Kg, Klol etc calculations. However I'm still struggling to get buffers. I understand that they maintain a constant pH with the addition of acid or Alkali, but I'm struggling to see how.

    Some reasons why I'm confused.

    |Does every buffer contain a Weak Acid/Conjugate Acid AND a Weak Base/Conjugate Base working together?
    A buffer solution consists of a weak acid and one of its salts(e.g ethanoic acid and sodium ethanoate) OR a weak base and one of is salts (e.g ammonia and ammonium chloride). The acid partially dissociates into H+ ions and the salt dissociates completely.
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    in these exams they seem to refer to a buffer as a mixture of the acid and its salt.
    some past paper i did asked this about ammonia, so a buffer solution of ammonia would be ammonia solution with ammonium nitrate, for example
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    Why would I use one over the other?
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    to bed!!
    wish i could do an all nighter and crack out this exam, but i cant do two all nighters in a row. (english exam on thurs morn)
    what freak does chemistry and english? oh yeah, me..
    theres me and one other person i think who do both. why why why did i think it would be a good idea
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    Does anyone have the Jan 2011 paper and markscheme thanks!
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    (Original post by cORBO3)
    Does anyone have the Jan 2011 paper and markscheme thanks!
    Search on the forum or in this thread, it's all over the place
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    (Original post by beckyxo)
    to bed!!
    wish i could do an all nighter and crack out this exam, but i cant do two all nighters in a row. (english exam on thurs morn)
    what freak does chemistry and english? oh yeah, me..
    theres me and one other person i think who do both. why why why did i think it would be a good idea
    I do both ;D
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    Think I'm pretty much sussed for this exam, might give everything a once over before the exam but apart from that I'm done! Good luck guys
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    Revision was going well but, somehow, i'm watching Tales of Mere Existence now...
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    I don't know if this question has been asked already (sorry if it has) but do we need to know a labelled diagram for the apparatus for reflux?
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    (Original post by Tetanus)
    :lolwut: you sure?
    Im sure ... its in my revision guide, and i have just checked it again . definitely
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    (Original post by parallal)
    I don't know if this question has been asked already (sorry if it has) but do we need to know a labelled diagram for the apparatus for reflux?
    I doubt it, they could bring it up I guess as it is synoptic... but that's past units really.

    If they do it's just, pear shape flask, anti-bumping granules, open top, flame, condenser
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    any1 got june 2010 paper ????????????? or know where to find it
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    (Original post by AGM)
    I doubt it, they could bring it up I guess as it is synoptic... but that's past units really.

    If they do it's just, pear shape flask, anti-bumping granules, open top, flame, condenser
    Ok, thanks.
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    I'm ready for the paper
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    (Original post by Adam9)
    any1 got june 2010 paper ????????????? or know where to find it
    Here you go. It's the June 2010 paper for the new specification (F335) as well as the mark scheme
    Attached Images
  1. File Type: pdf June2010 (New).pdf (188.0 KB, 70 views)
  2. File Type: pdf ocr_56100_ms_10_gce_f335.pdf (322.1 KB, 51 views)
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    (Original post by Jhyzone)
    I'm ready for the paper
    I don't think I am. ): All of those reagents and conditions are so hard to remember.
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    (Original post by parallal)
    Here you go. It's the June 2010 paper for the new specification (F335) as well as the mark scheme
    THANKS, much appreciated
 
 
 
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