Posted by Tracy on .
I'm currently in a kinetics class and I am trying to do a prelab for a lab that we haven't learned the material for yet and I'm really stuck, and we unfortunately don't have a textbook for the class so I was hoping someone could help. We have the compound m-xylene and it gives the structure (you can get it on the internet too), first it asks how many non-equivalent protons there are...now I know the definition of non-equivalent protons but I have no idea how you can tell where the spins are equal or not...is it because it is the same element? The second question asks what coupling pattern you would expect based on the structure...now as far as I can tell it is based on the non-equivalent protons is it not? That deteremines how many peaks it has? I'm not sure. Lastly, they want a sketch of the 1H spectra showing the splitting pattern and relative position of each signal...this I'm totally lost at. I know the amount of peaks should be equal to the non-equivalent protons..or so I think..but I don't know how you would know how many bumps in the peak, or where the signals would be...I'm so lost.
See if this will help.
That does help for at least seeing what the spectrum will look like, but I still don't get a few things...how do you know what the equivalent protons are? How do I know the coupling pattern? Would it be a triplet because it has 3 peaks..or is that something totally different? And how would I know the position of each signal on the spectra, I mean i would assume was a peak but how would I tell which is which? Would that mean there is 3 non equivalent protons?