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    (Original post by susan23)
    gradiet at what point?
    The tangent you use to figure out the initial rate, ie.(0,0.010)
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    Say you only worked out 2 half lives as 190 & 210 so said it was second order and wrote all the rest correct and folled through. With ECF how many marks do you think you would lose?
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    (Original post by pavan pong)
    it didnt say it was endothermic did it? it said it took place at zero so must it be exo as it requires no energy
    No but the process of going from a solid to a liquid means breaking bonds, which is endothermic, and if you think about the process in itself you have to put energy in in order to make something melt.. 0 degrees is just an arbitrary value we have created, its actually 273 Kelvin..
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    (Original post by tessfoley)
    Say you only worked out 2 half lives as 190 & 210 so said it was second order and wrote all the rest correct and folled through. With ECF how many marks do you think you would lose?
    i think 2 or 3
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    (Original post by Sereni)
    Using lactic acid and its salt my ratio was 2.04:1
    1/2.04=0.49 so that's what I got.
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    Got so much wrong in this paper by the looks of things :/ don't think i'll be getting into even my insurance choice now :/
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    (Original post by blush.ox)
    :yy: thats what i did, although i did it wrong initially lol. What did you get for the pH on the opp page?
    Well most people got 2.1 or something but I got 1.92/1.82 so I did something wrong somewhere. I hope I get marks for working
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    I was kinda worried about the exam because I hadn't really done much revision, but it surprisingly wasn't that difficult.
    The topics were all ones that I remembered being taught, and the rest, I worked out intuitively - and some logical thought.

    Overall, I'd say not bad. Expecting 80%-90%.

    Also, this is science guys. It's not merely an exam. The questions weren't that difficult if you had been trained to think critically - though, that would not entirely be the fault of you, as most curriculums focus more on solving repititive sets of problems rather then thinking critically and applying what you know to more complex phenomena and context.
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    (Original post by Kalamari Dave)

    ?) % of Cu in Brass question
    Equations with state symbols:
    Cu (s) + 4HNO3 (l) --> Cu(NO3)2 (aq) + 2NO3- (aq) + 2NO + 2H2O
    Cu2+ + 2I- (aq) --> CuI (s) + 0.5 I2 (aq)
    (one more which i can't rememebr)


    I think it was removing excess acid with OH-
    so it was
    H+ + OH- --> H2O
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    does anyone know the typical grade boundaries for this paper?
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    (Original post by middle92)
    **** got [br] second order, but i think i got the working for the rest right.ECF ECF! drew a tangent to the initial rate then concentration decrease over time?
    I got second order, too. Do we get ECF throughout?
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    (Original post by 786girl)
    58/100 = A

    plus a tangy sweet as compensation for mental torture.
    did you make that up? I certainly hope its around that
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    (Original post by mathsmad)
    This is the second paper by OCR in a week that has just been way of the mark. We need to something about it.
    The people who created the group on facebook for biology are telling us to stop moaning on the biology page (rightly so) ... someone make a chemistry facebook page? i dont have facebook (dont trust meself to not speand my life on it^^)
    In my opinion... The governments are tied to the exam boards. If we mess up this year and dont get in.. we will be paying the higher tuition fees. So they win.
    THIS HAS TO STOP.Anybody with me?
    i had this exact discussion with the people from my class after the exam. i hate to be all conspiracy theorist, but it seems a TINY bit odd that the year before uni fees skyrocket to £9000 per year all the exams are ridiculously difficult. compare F324 and F325 this year with 2010 and there's a huge difference in the difficulty of the papers.

    thanks OCR.
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    (Original post by Kalamari Dave)
    -
    I disagree with your monomer, they wanted 4,4 bipy not 2,2 bipy
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    (Original post by boba)
    does anyone know the typical grade boundaries for this paper?
    Last two times it was ~60/100 raw marks for an A (120 UMS).
    Don't know how its gonna be this time, quite a few people thought it was good, quite a few thought it was horrible.
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    Anyone else got F224 next week. I dont even feel like revising anymore. I was planning to go through that again for the 3rd time but after this i just feel OCR is going to **** us all again
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    (Original post by amyyy24)
    I think it was removing excess acid with OH-
    so it was
    H+ + OH- --> H2O
    It was more complicated as it formed a solid precipitate so it didnt cancel
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    Does any one have an answer for the Kc Calculation and the hydration of Mg2+
    I got Kc as 45
    And the hydration of Mg2+ as -2300 or something similar can't remember exact value
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    (Original post by Heatheroink123)
    For the weakest acid to strongest acid thing, I got ethanoic as the weakest and pyruvic as the strongest. My method being the higher the pKa, the lower the Ka and the lower the Ka, the weaker the acid. Can anyone confirm this?
    I agree I did ka = 10^-pka and the higher the ka the more dissociation and stron ger the acid.
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    (Original post by Jtking3000)
    I disagree with your monomer, they wanted 4,4 bipy not 2,2 bipy
    Oh ****, thanks for point that out.
    That's a mark down the drain for me then!
 
 
 
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