UNIT 4 - NMR

Question 1

What does absorption of radiation in the radio frequency region of the electromagnetic spectrum cause?

Answer 1

Proton nuclei to flip from the lower to the higher energy alignment. As they fall back down, the emitted radiation is detected and plotted onto a spectrum.

Question 2

How can NMR spectra be obtained?

Answer 2

Using low-resolution or high-resolution NMR.

Question 3

What does high-resolution NMR use?

Answer 3

Higher radio frequencies than those used in low-resolution NMR and provides more detailed spectra.

Question 4

In high-resolution protein NMR, what does an interaction with proton atoms on neighbouring carbon atoms result in?

Answer 4

Splitting of peaks into multiplets. The number of proton atoms on neighbouring carbon atoms will determine the number of peaks within a multiplet and can be determined using the n +1 rule. where n is the number of proton atoms on the neighbouring carbon atoms.