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Topic: NMR Help  (Read 5215 times)

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Offline AngieUK77

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NMR Help
« on: May 29, 2008, 03:56:59 PM »
Can anyone tell me what would happen to an NMR spectrum of 2-methyl-1-propanol if it was to become contaminated with benzene?

And if you know how to calculate the relative degree of benzene contamination that would be really great. I don't want you to do it for me just refresh my mind as to how it is done.

Thanks in advance for any help.

Offline macman104

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Re: NMR Help
« Reply #1 on: May 29, 2008, 06:46:37 PM »
I imagine you would see a peak in the nmr for benzene?  Was there something more you wanted?  You could tell the relative concentration by comparing the integration of the bezene peak with the integratin of one of your peaks.

Offline gericox

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Re: NMR Help
« Reply #2 on: May 30, 2008, 07:46:08 AM »
You will see in 1H NMR :
for 2-methyl-1-propanol : CH3 (doublet, # 1ppm, 6H) ; CH (multiplet, #2.5-3 ppm, 1H) ; CH2 (#doublet , 3-3.5 ppm, 2H) and OH mobile
for benzene :1 singulet, # 7-7.5 ppm, 6H

Quantitation :
take integration of methyl (for exemple ) INT1 =(integration/6)*Mw of 2-methyl-1-propanol
take integration of benzene : INT2= (integration/6)*Mw of benzene

content of benzene= 100*INT2/(INT1+INT2)   (%)

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