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    (Original post by quinn f)
    there wasn't a peak for C=C I checked, I think it was O-H
    There was a peak for C=C it was between 1600 and 1700
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    (Original post by zigocarn)
    The reason they gave lines if because there was two parts to the question. One required an explanation and hence lines were given.
    what's your point?

    we're talking about whether or not a diagram of the mechanism was needed as they didn't give any space to draw it for the 7 marker
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    (Original post by hasbro7)
    Hey guys. I believe for the thin layer catalyst question, it was so that the gases produce can diffuse easily out of the engine- but not sure once again and there could indeed be multiple answers. For the reason about the data book value being different- I think either the heat capacity of the copper calorimeter isn't included OR water is formed in the gaseous state should be enough to get the mark.
    I put that it increases surface area, therefore rate of reaction, and that a thin layer is used because the metals can be expensive. Also for the data book Q I put impure methanol? Not sure
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    (Original post by Splaffie)
    There was a peak at 1620-1680 signifying a c=c bond, however in terms of actual functional groups it was an alcohol
    what was the question exactly? c=c is also a functional group
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    (Original post by hasbro7)
    Hey guys. I believe for the thin layer catalyst question, it was so that the gases produce can diffuse easily out of the engine- but not sure once again and there could indeed be multiple answers. For the reason about the data book value being different- I think either the heat capacity of the copper calorimeter isn't included OR water is formed in the gaseous state should be enough to get the mark.
    The thin layer was used because the metals were expensive rare earth metals, using a thin layer over a honeycomb structure means that there is a large surface area with a small volume of expensive metal for the most efficient amount of catalytic conversion because lots of successful collisions blabla

    The data book value is different because it uses average bond enthalpy
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    (Original post by quinn f)
    I put that it increases surface area, therefore rate of reaction, and that a thin layer is used because the metals can be expensive. Also for the data book Q I put impure methanol? Not sure
    I also added in the surface area bit for that question to be on the safe side so we should be good. And not sure about impure methanol...
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    for the question about testing for oleic acid, I put Na2CO3... Might of read the qu wrong was it the test for unsaturation or what?
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    What did you guys get for the mcq with the percentage masses given and it asked you which it could have been of ethanol, ethanoic acid, methanol and methanoic acid?
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    (Original post by SM-)
    Did anyone get 1.01 x 10^25 or number of molecules?
    Yep I got
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    (Original post by sgill23)
    for the question about testing for oleic acid, I put Na2CO3... Might of read the qu wrong was it the test for unsaturation or what?
    Bromine water Orange -> colourless in the presence of double c=c bonds
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    (Original post by haes)
    There was a peak for C=C it was between 1600 and 1700
    Oh? In which case I imagine C=C and O-H will both be accepted as long as you said the right region for the bit after
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    (Original post by quinn f)
    Oh? In which case I imagine C=C and O-H will both be accepted as long as you said the right region for the bit after
    For the Kc question, how many marks was it?
    Also, were you given the equilibrium mole composition and then just had to divide everything by the volume?
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    (Original post by quinn f)
    What did you guys get for the mcq with the percentage masses given and it asked you which it could have been of ethanol, ethanoic acid, methanol and methanoic acid?
    ethanoic acid
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    (Original post by metrize)
    Was the displayed thing for the prop-1,2-iol reflux
    COOHCOCH3

    yeah i got that, and then did you get a an aldehyde and ketone for the one where it said 'draw the one that potassium dichromate wasn't in excess'
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    (Original post by quinn f)
    What did you guys get for the mcq with the percentage masses given and it asked you which it could have been of ethanol, ethanoic acid, methanol and methanoic acid?
    I put ethanoic acid because its exactly double the empirical formula calculated from the percentage masses
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    (Original post by zigocarn)
    For the Kc question, how many marks was it?
    Also, were you given the equilibrium mole composition and then just had to divide everything by the volume?
    I'm not sure exactly, I think it was 2 marks for each part? And yeah, just divide by volume to get conc then sub in
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    (Original post by will090998)
    yeah i got that, and then did you get a an aldehyde and ketone for the one where it said 'draw the one that potassium dichromate wasn't in excess'
    yeah I also got this
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    (Original post by quinn f)
    I'm not sure exactly, I think it was 2 marks for each part? And yeah, just divide by volume to get conc then sub in
    Oh right.
    Did you multiply by 1000, when you did moles/vol btw?
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    The exam wasn't easy in my opinion. Some questions were quite hard. The grade boundaries might look something like this:

    A-59
    B-53
    C-49
    D-44
    E-38
    Give or take some marks
    Remember there aren't any resists to skew the marks higher as well and these are the first set of exams for us!
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    (Original post by Gswp)
    what's your point?

    we're talking about whether or not a diagram of the mechanism was needed as they didn't give any space to draw it for the 7 marker
    you draw it on the lines or ask for additional paper if yu run out of space
 
 
 
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