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Topic: Need help with practical NMR calculation  (Read 2432 times)

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Offline poonilization

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Need help with practical NMR calculation
« on: April 01, 2015, 11:25:10 AM »
Hey guys, i'm kinda stumped on a simple question and i feel like im being an idiot.

so heres the question:



So i've calculated delta E for a proton at 7 T using the magnetogyric ratio 26.75x107, and got the answer 1.97x10-25 J
Now for deuterium, i use the magnetogyric ratio 4.11x107 and get 3.03x10-26 J. However in lectures i was told the answer should be 3.28x10-26 J. Any ideas where im going wrong?

Similarly, for part b.



i get 5.95x10-25 which is correct. However again, when i try the same calculation for deuterium i get 9.15x10-26 J and was told the answer should be 9.88x10-26 J.

Any help would be much appreciated.

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« Last Edit: April 01, 2015, 11:55:43 AM by Dan »

Offline mjc123

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Re: Need help with practical NMR calculation
« Reply #1 on: April 02, 2015, 05:30:01 AM »
I agree with your answers. The ratio of the "right" answer to your answer is the same in each case. It is also the ratio of 4.44 to 4.11. I wonder if the question-setter accidentally typed 4.44 x 10-7 into his calculator?

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