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    (Original post by wwwwwwwwwwwf)
    I got 860kJmol -1 for the born haber cycle for formation of BaCl2 and go -22.94 for the gibbs free energy change
    Same but i think it was -860?
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    (Original post by wwwwwwwwwwwf)
    I got 860kJmol -1 for the born haber cycle for formation of BaCl2 and go -22.94 for the gibbs free energy change
    Excellent I got the same, though I wrote the Gibbs free energy as J instead of KJ, but it did start with a 2.
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    (Original post by Formless)
    Same but i think it was -860?
    Yeah i meant that my bad, formation is always exothermic so ya
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    Did anyone else get a negative value for emf of the two half cells Copper and Iron? And no reaction for the vanadium & iron?
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    (Original post by Faisalshamallakh)
    Did anyone else get a negative value for emf of the two half cells Copper and Iron? And no reaction for the vanadium & iron?
    the value was positive? i thought they do react
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    What was the positive electrode?
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    i put Whatever the left hand electrode was! i think fe maybe?
    (Original post by Pixie1234)
    What was the positive electrode?
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    (Original post by ALevel Student 1)
    No, I got 0.78V and I thought it was nickel not vanadium- cant remember seeing vanadium anywhere. But either way there was no reaction for that second one as it was a trick where it was Fe 2+ not Fe
    Sorry my bad nickel! I had a positive value at first but I remembered that whatever half-cell is on the right hand side is the one being reduced. So I switched it over to right minus left to get a negative emf.
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    (Original post by Faisalshamallakh)
    I had a positive value at first but I remembered that whatever half-cell is on the right hand side is the one being reduced.
    Yeah it usually is, but wasn't in this case :/
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    (Original post by wwwwwwwwwwwf)
    I got -860kJmol -1 for the born haber cycle for formation of BaCl2 and go -22.94 for the gibbs free energy change

    Also got 59.5% copper content in the brass and 0.083 for NaOH concentration

    Got 4.9x10-5 somewhere too I think, aswell as 7.0x105?
    Got all of those same values apart from the Gibbs, forgot to convert the temperature :/
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    (Original post by marethyu)
    -20 kJ ish



    Yeah I'm almost certain its starch



    k(h+)(CH3COOCH3)
    Awwww crap i only put the H+ in
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    (Original post by wwwwwwwwwwwf)
    Yeah i meant that my bad, formation is always exothermic so ya
    Would you get the full 4 marks just for getting that value? Thought 4 marks was a lot just for that
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    (Original post by sumeyyatontus)
    Would you get the full 4 marks just for getting that value? Thought 4 marks was a lot just for that
    Hmm, i guess you had to remember the formula and get in correct for 1mark, use correct values for the formula (and remember to mulitply the energies for chlorine) for 1 mark.. uh then one for answer and another mark for correct sign/units
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    (Original post by wwwwwwwwwwwf)
    Hmm, i guess you had to remember the formula and get in correct for 1mark, use correct values for the formula (and remember to mulitply the energies for chlorine) for 1 mark.. uh then one for answer and another mark for correct sign/units
    How many marks would i lose in total if I had the rate equation as only with (H+)?
    As my calculation after it also used the equation?
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    (Original post by Firestartc)
    How many marks would i lose in total if I had the rate equation as only with (H+)?
    As my calculation after it also used the equation?
    I was talking about the born-haber cycle for BaCl2 in that post. Im not sure what question you mean:/
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    (Original post by wwwwwwwwwwwf)
    I was talking about the born-haber cycle for BaCl2 in that post. Im not sure what question you mean:/
    The first question, the one which should be rate = k(h+)(Ch3COCh3)
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    (Original post by Firestartc)
    How many marks would i lose in total if I had the rate equation as only with (H+)?
    As my calculation after it also used the equation?
    I assume there will be error carried forward marks for the next part, so just 1 mark I think
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    What letters did everyone get for the 2 graphs? I got W and Y, not sure if the second one is right though
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    (Original post by sumeyyatontus)
    What letters did everyone get for the 2 graphs? I got W and Y, not sure if the second one is right though
    HCl at 0.1 mol which was W

    and Ch3COOH (or w.e it was) at 0.001 which i think was Y but cant remember
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    I don't think I did very well in this. I think it was harder than last years and didn't help I messed up my timing.

    For some reason I got stuck on simple questions like q3 where it was asking something about how the your answer to born haver cycle proves what the text is saying about hydrogen. I also got a different value for Gibbs!!

    There was another confusing question but I can't remember it! Can someone make a unofficial mark scheme or list the questions with the amount of marks please!
 
 
 
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