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    (Original post by marcusman97)
    Will alcohol + Na -> o- na+?
    no alcohol not strong enough acid to firm a salt


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    (Original post by ReeceM1)
    Wouldn't the peaks for C11 and C10 both be triplets? Because there are 2 H in each environment and both are adjacent to a H?
    No because each carbon only has one H attached to it. There's only 2 Hs in each environment because of the symmetry
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    Just wanted to pass by and say good luck to everyone for F324 :lol:
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    (Original post by alow)
    Calm down dear. There's nothing wrong with learning a bit more chemistry.



    For aromatic systems there is usually coupling between "neighbouring protons" with a relatively large splitting, and then coupling across the ring with smaller splitting (this is not always seen if the NMR is not taken at high enough resolution).

    For that I would say:

    2- Singlet (nothing close)
    4- Doublet (couples with 5)
    5- Doublet (couples with 4)

    (these may display cross-ring coupling to make 2 a doublet and 4/5 doublets of doublets).

    10- Doublet (couples with 11)
    11- Doublet (couples with 10)

    (these may also be doublets of doublets due to small cross-ring coupling).
    would 2 and 4,5 being very close to each other? cuz from what i see in the diagram i think the singlet and one of the doublets overlapped each other.
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    (Original post by alow)
    I never said it did, but it is correct.
    But this thread is about F324. And it's the night before the exam! Most students just want to get as many marks as possible on the paper, not learn new unnecessary stuff now!
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    (Original post by Chem1stry101)
    No because each carbon only has one H attached to it. There's only 2 Hs in each environment because of the symmetry
    Ohhh, I thought because the are two protons in the same environment, and each of these is adjacent to a proton that means that there's are two adjacent protons therefore a triplet?
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    (Original post by alow)
    Calm down dear. There's nothing wrong with learning a bit more chemistry.



    For aromatic systems there is usually coupling between "neighbouring protons" with a relatively large splitting, and then coupling across the ring with smaller splitting (this is not always seen if the NMR is not taken at high enough resolution).

    For that I would say:

    2- Singlet (nothing close)
    4- Doublet (couples with 5)
    5- Doublet (couples with 4)

    (these may display cross-ring coupling to make 2 a doublet and 4/5 doublets of doublets).

    10- Doublet (couples with 11)
    11- Doublet (couples with 10)

    (these may also be doublets of doublets due to small cross-ring coupling).
    I appreciate that, sorry, it's only because the exam's tomorrow I'm stressing myself out over your more complex method sry
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    (Original post by lai812matthew)
    would 2 and 4,5 being very close to each other? cuz from what i see in the diagram i think the singlet and one of the doublets overlapped each other.
    The shifts would be pretty close, yeah.

    (Original post by Chem1stry101)
    But this thread is about F324. And it's the night before the exam! Most students just want to get as many marks as possible on the paper, not learn new unnecessary stuff now!
    It's the night before the exam. If you're not prepared by now you're a bit ****ed.
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    Do we need to memorise the monomers of all the polyamides/polyesters mentioned in the textbook like Terylene?
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    (Original post by fannehh)
    Do we need to memorise the monomers of all the polyamides/polyesters mentioned in the textbook like Terylene?
    It says on the specification that we don't need to remember them.
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    (Original post by itsConnor_)
    I appreciate that, sorry, it's only because the exam's tomorrow I'm stressing myself out over your more complex method sry
    It's fine. I have a bit of a pet peeve about how NMR is taught at A Level, especially when it's really obvious what they tell you is wrong from other parts of the course (e.g. looking at the electron density diagram for phenol in the F324 book it's obvious the protons are quite inequivalent). Plus I don't think my teacher really ever taught how to work out which of several similar protons will be more/less shifted, I did all of that alone.
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    (Original post by Chem1stry101)
    But this thread is about F324. And it's the night before the exam! Most students just want to get as many marks as possible on the paper, not learn new unnecessary stuff now!
    I fully agree, the exam's in 14 hours!
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    (Original post by fannehh)
    Do we need to memorise the monomers of all the polyamides/polyesters mentioned in the textbook like Terylene?
    Nah they've never required you to in any of the past papers, they'll tell u the monomers and you will have to join them together
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    (Original post by ReeceM1)
    It says on the specification that we don't need to remember them.
    Great, thanks!
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    (Original post by alow)
    It's fine. I have a bit of a pet peeve about how NMR is taught at A Level, especially when it's really obvious what they tell you is wrong from other parts of the course (e.g. looking at the electron density diagram for phenol in the F324 book it's obvious the protons are quite inequivalent). Plus I don't think my teacher really ever taught how to work out which of several similar protons will be more/less shifted, I did all of that alone.
    they tell you the splitting is quintet with CH2-CH2-CH2
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    (Original post by ReeceM1)
    Ohhh, I thought because the are two protons in the same environment, and each of these is adjacent to a proton that means that there's are two adjacent protons therefore a triplet?
    If you have symmetry and one environment is mirrored elsewhere in the molecule, just look at one side for the splitting pattern.

    Eg if you had CH3-CH2-O-CH2-CH3 it is symmetrical. So only 2 H environments. The CH3 peak would be a triplet due to the neighbouring CH2, and the CH2 would be a quartet due the neighbouring CH3
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    (Original post by fannehh)
    Do we need to memorise the monomers of all the polyamides/polyesters mentioned in the textbook like Terylene?
    i hope they will at least give a formula before asking us questions about it because i cannot remember !
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    (Original post by lai812matthew)
    they tell you the splitting is quintet with CH2-CH2-CH2
    It can be if the molecule is totally symmetric about that point. If not just nonononono.
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    (Original post by alow)
    It can be if the molecule is totally symmetric about that point. If not just nonononono.
    it is attached with different functional groups at the end, so an asymmetric one, my teacher got very angry about it, and said if you make the same mistake as the examiners did, he would kill all of us.
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    (Original post by lai812matthew)
    it is attached with different functional groups at the end, so an asymmetric one, my teacher got very angry about it, and said if you make the same mistake as the examiners did, he would kill all of us.
    You're lucky to have a teacher who both understands the content and gives a crap. Depending on the functional groups the coupling could be all over the place, let alone a quintet.
 
 
 
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