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    do you think they will be fine with the mechanism as a "description of the mechanism"? because it sort of is
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    (Original post by wwwwwwwwwwwf)
    Can someone remember what the questions for question 4 were (apart from the NMR and mass spec bits)
    Something about explaining NMR and IR spectra?
    What the X axis is - answer was "retention time"
    Finding out percentage volume of A - answer I believe was 20%
    And something about the difference in what information you can find from thin layer chromatography and gas chromotography

    Not sure if I've missed anything out
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    (Original post by sumeyyatontus)
    Something about explaining NMR and IR spectra?
    What the X axis is - answer was "retention time"
    Finding out percentage volume of A - answer I believe was 20%
    And something about the difference in what information you can find from thin layer chromatography and gas chromotography

    Not sure if I've missed anything out
    Yeah thats right I remember now, thanks! I had 20% too
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    (Original post by wwwwwwwwwwwf)
    Na it gives you methyl bezene

    http://www.chemguide.co.uk/mechanism...b/fcalkyl.html
    WTF! my teacher taught it wrong WOW! i'm done.
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    I really was unsure for the isomers at the start too because they all had to have a double carbon bond since they all declourised bromine, but i couldn't get the Hydrogens to match the orginal compound (if you were supposed to that). Anyone remember what they did?

    I remember the isomers i did were ketones with double bonds.
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    (Original post by wwwwwwwwwwwf)
    I really was unsure for the isomers at the start too because they all had to have a double carbon bond since they all declourised bromine, but i couldn't get the Hydrogens to match the orginal compound (if you were supposed to that). Anyone remember what they did?

    I remember the isomers i did were ketones with double bonds.
    I drew one 1-ene isomer, and the 2-ene isomer that can also form displays E-Z isomerism. So one 1-ene isomer and the E and Z forms of the 2-ene isomer, making 3 in total. Not sure if that was the right answer, but it was the only one I could make that worked.
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    What did you guys put for the question which asked about optical isomers and why it gave a certain figure (30 something)? Sorry this is described really badly!
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    I said because the figure they gave was the difference between the fructose and glucose, so it meant that there was no sucrose left!
    (Original post by Pixie1234)
    What did you guys put for the question which asked about optical isomers and why it gave a certain figure (30 something)? Sorry this is described really badly!
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    Did you say that it formed a racemic mixture or not?
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    Ayy i did lmao
    (Original post by Pixie1234)
    Did you say that it formed a racemic mixture or not?
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    What about the solubility question?
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    (Original post by DragonRider17)
    I drew one 1-ene isomer, and the 2-ene isomer that can also form displays E-Z isomerism. So one 1-ene isomer and the E and Z forms of the 2-ene isomer, making 3 in total. Not sure if that was the right answer, but it was the only one I could make that worked.
    Did exactly this, saw it an past paper and pretty sure this is correct
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    (Original post by Pixie1234)
    What did you guys put for the question which asked about optical isomers and why it gave a certain figure (30 something)? Sorry this is described really badly!
    You had to add up the angle of rotations, -90something degrees and +50something. Which gives you the net rotation of 30 Something as mentioned in the questions
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    (Original post by Pixie1234)
    What about the solubility question?
    The alcohol group in the compound. h covalently bonded to O (EN Negative) blah blah it can form hydrogenbonds with water molecules, due to OH present in Water
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    There was a question with a phenylamine attached to an methyl group and then an OH. What happens when you react it with ethanoyl chloride. do you form an ester on one end and an N substituted amide on the other side?
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    Name:  Phenol.PNG
Views: 100
Size:  40.1 KB
    Carboxylic acid does produce bubbles as co2 is produced when reacted with Na2CO3, Phenol has no reaction therefore statement is false
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    (Original post by Formless)
    There was a question with a phenylamine attached to an methyl group and then an OH. What happens when you react it with ethanoyl chloride. do you form an ester on one end and an N substituted amide on the other side?
    Oh damn!!!! I only changed the amine group
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    To those of you that are new to this thread, Hitler has responded to the CH4 Exam:

    https://www.youtube.com/watch?v=FfAJvji4Bgs

    definitely worth a watch if you found it you need some cheering up, incase you found it as difficult as I did
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    I want to take a stab in the dark and say grade boundaries will be around 59 for an A, 53 for a B, 47 for a C and so on.
    I think a lot of people didnt just find the questions difficult but also the way the exam was actually presented, it was nothing like I'd ever experienced before! I think I got full marks on Q1 because the questions were straight forward and actually on the spec. I couldn't get my head around the concepts in Q2. I didnt say Phenol wasn't acidic enough to react with sodium carbonate, and I also conpletely forgot about amino acids being zwitterions so I struggled on that as well. Q3 was incredibly difficult, but I think the majority of the country thought the same so this will be the question that brings the grade boundaries down. I made a silly mistake in Q4 and my answers about NMR/IR and GC/TLC are hit and miss. Q5 was good but I didnt understand why it said 'describe the mechanism' so I just drew it. I wasn't too sure what reflux meant so I just put boiling the liquid to a vapour and cooling to condense. Then the how science works question was dodgy, those answers are always hit and miss. Poor exam.
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    (Original post by matt1997x)
    I want to take a stab in the dark and say grade boundaries will be around 59 for an A, 53 for a B, 47 for a C and so on.
    I think a lot of people didnt just find the questions difficult but also the way the exam was actually presented, it was nothing like I'd ever experienced before! I think I got full marks on Q1 because the questions were straight forward and actually on the spec. I couldn't get my head around the concepts in Q2. I didnt say Phenol wasn't acidic enough to react with sodium carbonate, and I also conpletely forgot about amino acids being zwitterions so I struggled on that as well. Q3 was incredibly difficult, but I think the majority of the country thought the same so this will be the question that brings the grade boundaries down. I made a silly mistake in Q4 and my answers about NMR/IR and GC/TLC are hit and miss. Q5 was good but I didnt understand why it said 'describe the mechanism' so I just drew it. I wasn't too sure what reflux meant so I just put boiling the liquid to a vapour and cooling to condense. Then the how science works question was dodgy, those answers are always hit and miss. Poor exam.
    I really hope you're right with those grade boundaries! I'm hoping for no more than 60/61 for an A due to how many silly mistakes I made due to the stupid layout of some of the questions

    Does anyone know if teachers have a copy of the paper yet?
 
 
 
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