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    Need help with this question. Name:  xoxoxo.png
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Size:  32.0 KB Have I counted the proton environments right here? I counted 5, so surely there are 5 carbon peaks but the answer says only 2.

    Thanks
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    I think the question's answer is right, if you look region 2 has a carbon connected to it with 3 hydrogens on it, but every other carbon has just 1 hydrogen coming off it, so it might be that you've got one carbon atom with 5 hydrogens attached to the other carbon atoms next to it and the others each have 2 on the adjoining carbon atoms. I think by 2 peaks it means 2 different peaks, i.e. if they've all got the same environment that would count as one peak. Don't trust me fully on that though, I could easily be wrong.
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    (Original post by RallySPORT)
    I think the question's answer is right, if you look region 2 has a carbon connected to it with 3 hydrogens on it, but every other carbon has just 1 hydrogen coming off it, so it might be that you've got one carbon atom with 5 hydrogens attached to the other carbon atoms next to it and the others each have 2 on the adjoining carbon atoms. I think by 2 peaks it means 2 different peaks, i.e. if they've all got the same environment that would count as one peak. Don't trust me fully on that though, I could easily be wrong.
    Yeah you're wrong.

    There are 5 environments. Here is the (simulated) 13C NMR of TNT:



    Here's a quick simulated NMR I did myself (don't pay too much attention to the shifts, just to the distinct peaks):



    However for proton environments, there are two (as only the methyl and 3 carbons have protons attached):

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    (Original post by RallySPORT)
    I think the question's answer is right, if you look region 2 has a carbon connected to it with 3 hydrogens on it, but every other carbon has just 1 hydrogen coming off it, so it might be that you've got one carbon atom with 5 hydrogens attached to the other carbon atoms next to it and the others each have 2 on the adjoining carbon atoms. I think by 2 peaks it means 2 different peaks, i.e. if they've all got the same environment that would count as one peak. Don't trust me fully on that though, I could easily be wrong.
    Hey, I realise where I have gone wrong now. Thanks. So does this molecule have 5 carbon environments?
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    (Original post by alow)
    Yeah you're wrong.

    There are 5 environments. Here is the (simulated) 13C NMR of TNT:

    Where can you find this app to check the no of environments?
    So No of H environments : 2 No of carbon envirnonment : 5 or 7?

    Thanks again
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    (Original post by alow)
    Yeah you're wrong

    well rip me
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    (Original post by coconut64)
    Where can you find this app to check the no of environments?
    So No of H environments : 2 No of carbon envirnonment : 5 or 7?

    Thanks again
    I use ChemDoodle to generate NMRs, but it's not that good at predicting shifts (although they're not too far off), only for showing the number of environments.

    I edited my last post to include a simulated 1H NMR, there are 2 environments.
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    (Original post by alow)
    I use ChemDoodle to generate NMRs, but it's not that good at predicting shifts (although they're not too far off), only for showing the number of environments.

    I edited my last post to include a simulated 1H NMR, there are 2 environments.
    So there are 7 carbon environments in total? Why isn't the carbon environment the same on the carbon atom attaching to NO2 ?? I don't quite get it... This is very annoying but pls help me!!

    THXX
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    (Original post by coconut64)
    So there are 7 carbon environments in total? Why isn't the carbon environment the same on the carbon atom attaching to NO2 ?? I don't quite get it... This is very annoying but pls help me!!

    THXX
    There are 5 carbon environments. There are 5 peaks in the NMR.
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    (Original post by alow)
    There are 5 carbon environments. There are 5 peaks in the NMR.
    Why does your stimulated image show 7? Is my labelling right here? Name:  hhhh.png
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    (Original post by coconut64)
    Why does your stimulated image show 7? Is my labelling right here? Name:  hhhh.png
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    It doesn't. It shows 5.
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    (Original post by alow)
    It doesn't. It shows 5.
    Right, so there are 5 peaks but why is there a 7 labelled next to the molecule?

    Also have I labelled my molecules right??
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    (Original post by coconut64)
    Right, so there are 5 peaks but why is there a 7 labelled next to the molecule?

    Also have I labelled my molecules right??
    That's just counting the carbons... Look at the spectrum...

    Your labelling is fine.
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    (Original post by alow)
    That's just counting the carbons... Look at the spectrum...

    Your labelling is fine.
    Cool, thats more reassuring. Also I have just downloaded that chemdoodle thing but I am so clueless as to how to use it. So just wondering if you know other apps that can do the same thing?

    Thank you so much
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    (Original post by coconut64)
    Cool, thats more reassuring. Also I have just downloaded that chemdoodle thing but I am so clueless as to how to use it. So just wondering if you know other apps that can do the same thing?

    Thank you so much
    ChemDraw might be able to but imo it's more difficult to use.
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    (Original post by alow)
    ChemDraw might be able to but imo it's more difficult to use.
    Chemdraw can do it, but I don't like it as a piece of software :biggrin:
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    (Original post by MexicanKeith)
    Chemdraw can do it, but I don't like it as a piece of software :biggrin:
    Yeah I'm not a fan of it either. And last time I used it drawing Bezier curves was stupidly difficult for mechanisms.
 
 
 
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