S3.2.10 1H NMR - how to determine number of peaks (HL)

In this video, I take a look at how to determine the number of peaks on a 1H NMR spectrum of an organic compound by looking at its structure formula. Note that I do not cover splitting of the peaks in this video as this covered in the HL part of the syllabus.

[@slimshady1394]

I am officially done with all chemistry topics!!! *-* wow. Thank uu MSJCHEM!
Now let's solve some past papers) !
Have an exam on 14th May, fingers crossed

[@MSJChem]

Best of luck in your exam

[@XenSolation.]

how was it

[@MSJChem]

?

[@bellamatela4273]

Thank you for the videos, you make IB chemistry so simple.

[@theeargasmchannel]

god bless you. I've been struggling with this so much! thank you!!

[@MSJChem]

Glad I could help.

[@ninafonteneaux6353]

thank you for updated video and the explanation of "chemical environment"

[@vishalraghuprakash6873]

this man is a god

[@veeeeeeee9908]

Thank you so much. These videos are helpful but at 3:17, why is there no peak at 0.9-1.0 range for -CH3?

[@MSJChem]

It is due to a phenomenon called deshielding. Knowledge of this is not required in IB chemistry but it is useful to know.
"Deshielding: The electrons around the proton create a magnetic field that opposes the applied field. This reduces the field experienced at the nucleus and therefore decreases the frequency required for the absorption. Therefore the chemical shift (delta /ppm) will change depending on the electron density around the proton. Since electronegative groups decrease the electron density, there will be less shielding (ie. deshielding) and the chemical shift will increase."
www.mhhe.com/physsci/chemistry/carey5e/Useful/nmr.html#Deshielding

[@sharkas9965]

​@@MSJChem you just couldnt explain this in the video

[@Model_T800]

The chemical shift of CH3 as mentioned in the data booklet is 0.9-1.0. So, how does the peak at 2 indicate CH3?
I'm really confused. Can you please help?

[@MSJChem]

“Deshielding: The electrons around the proton create a magnetic field that opposes the applied field. This reduces the field experienced at the nucleus and therefore decreases the freqency required for the absorption. Therefore the chemical shift (delta /ppm) will change depending on the electron density around the proton. Since electronegative groups decrease the electron density, there will be less shielding (ie. deshielding) and the chemical shift will increase. “
www.chem.ucalgary.ca/courses/353/Carey5th/useful/nmr.html

[@aerodronia9694]

Thanks! It is really helpful

[@MSJChem]

+이준식준식 You're welcome.

[@jdog4673]

Give fortis an A

[@MSJChem]

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