Proton NMR - The Basics

[@penfila]

After watching all the A2 EDEXCEL CHEMISTRY UNIT 5 videos of yours, I have gained so much confidence for the first time. I am sure to rock my exams. Loads of thanks for all the help you are dedicating for us and I appreciate your time!

[@DoctorGamerr]

OMG this video has helped me out so much in understanding NMR! Thank you so much!!

[@namirairin1976]

You’re a life saver! Thank you so much!

[@MicrobeStudent]

this video is great thank you!

[@motayee97]

Hi, thanks a lot for these videos they're so helpful!!!! But i'm really struggling on this topic, Like when you talk about chemical shift for example at around 4:04 you say chemical shift comes at around 4ppm but on the table for H n.m.r ROH it says 0.5-5.0

[@AlleryChemistry]

+Mo Tayee Yes it is a very broad range. However in this example the H was the OH group as the integration data showed a value of 1. In reality you would not use NMR in isolation and other analytical techniques should be used to confirm the identity of a substance. The exam will select a molecule that can be determined with the spectra they give you.

[@motayee97]

+A Level Chemistry Revision by Allery Tutors Oh i think I understand now, so it'll be likely that if given a spec with a broad range, say for instance OH, it'll just be quite simple (not too simple because its chemistry!!!) to distinguish which proton is responsible for that peak and which is responsible for the others (taking into consideration shift, integration and No. of peaks), Thanks so much, living off these videos for the next couple months!!!

[@AlleryChemistry]

+Mo Tayee Yes that's right. So look out for integrations and splitting patterns! Keep up the hard work! It will all pay off.

[@HS-lz8wy]

Why can't we use H based solvents, I cannot find the answer anywhere. Or did I miss it in the video? Thanks!

[@NoorFarouq]

Will we be given the integration number always? I think that must be vital for questions on this...

[@camillehou5902]

why the second CH2 in the middle of right diagram doesn't have (0.9-1.7ppm)?and why those 9 protons (-CH3)also can't lie at 0.9~1.7 from data booklet~🤔

[@AlleryChemistry]

+Camille Hou Yes, C-H shift values can be higher than what is stated in the data book. This is due to them being in close proximity to electronegative elements.

[@zaynaba6626]

hello! do we need to be able to calculate the integration number for the new spec?

[@samiultr]

just incase you've been doing your a levels for 4 years, the answer is no.

[@AzizurRahman-wv4tq]

+A Level Chemistry Revision by Allery Tutors Hi, I understand a lot more of Proton NMR now after watching your tutorial (you don't know how long I've been looking for a video that shows how to determine the proton environments!!!). However, now that i'm starting to understand it now, I have a few questions. As you explained that despite the proton environment being the same of the protons on the second carbon from the right, the chemical shift will slightly be different (when comparing the two CH2 groups) due to the electronegativity of the O, then won't the chemical shift of the proton on the first carbon (CH3 group) from the left have a lower chemical shift than the protons of the other two CH3 groups since the carbon (the first one!) is furthest away from the O? PS Sorry for the long question! I hope its clear. I also have few more questions but I can't remember them but I will ask once I remember them. Thank you for the videos and keep it up!

[@AlleryChemistry]

+Azizur Rahman Thanks very much! Yes however the CH3 group you are referring to is the same distance away from the oxygen as the 2 branching CH3 groups. In fact all 3 CH3 groups are in the same environment hence the huge peak with an integration of 9. This is shifted the lease due to the distance from the O. Hope this helps!

[@aki957]

thanks

[@AlleryChemistry]

+Shah. F you're welcome!